Abstract
A grinding and/or cutting tool which has at least one surface region for a lateral grinding process and a surface region for a circumferential grinding process and/or a cutting process. The surface regions have different removal properties. The material properties of the surface regions differ in that the surface regions have different abrasive materials, grinding particle shapes, particle scattering patterns, particle sizes, degrees of hardness, structures, and/or binders. In one embodiment, the grinding and/or cutting tool has two of the surface regions for a lateral grinding process, and the two surface regions for a lateral grinding process are arranged at a distance from one another. The surface region for a circumferential grinding process or for a cutting process is arranged preferably between the two surface regions for a lateral grinding process.
Claims
1-15. (canceled)
16. A grinding and/or cutting tool, comprising: at least one surface region for face grinding; and a surface region for circumferential grinding and/or cutting, wherein the surface regions have removal properties differing from one another.
17. The grinding and/or cutting tool according to claim 16, wherein the surface regions differ in terms of material properties.
18. The grinding and/or cutting tool according to claim 17, wherein the surface regions have different abrasives, abrasive particle shapes, particle scatter, granules, degrees of hardness, structures, and/or binders.
19. The grinding and/or cutting tool according to claim 16, having two of the surface regions for face grinding, wherein the two surface regions for face grinding are arranged at a distance from each other and the surface region for circumferential grinding and/or cutting is arranged between the two surface regions for face grinding.
20. The grinding and/or cutting tool according to claim 19, wherein at least the surface region for circumferential grinding and/or cutting and the two surface regions for face grinding have different shapes and/or different material properties, wherein the two surface regions for face grinding also differ in terms of shape and/or material properties.
21. The grinding and/or cutting tool according to claim 16, wherein the surface region for circumferential grinding and/or cutting is at a radially outer edge of the grinding and/or cutting tool, wherein the surface region for circumferential grinding and/or cutting terminates the grinding and/or cutting tool radially outwardly.
22. The grinding and/or cutting tool according to claim 16, wherein the surface region for face grinding is shaped as a base of a circular cylinder or a lateral surface of a cone or a curved shape.
23. The grinding and/or cutting tool according to claim 22, wherein the surface region for the face grinding has a convexly curved shape.
24. The grinding and/or cutting tool according to claim 22, wherein the surface region for face grinding is shaped as the lateral surface of a cone and has an angle between surface lines of the surface region and an axis of a cone portion forming the surface region is >60.
25. The grinding and/or cutting tool according to claim 24, wherein the angle is >65.
26. The grinding and/or cutting tool according to claim 16, wherein the surface region for circumferential grinding and/or cutting is at least in part shaped as a lateral surface of a right circular cylinder or a cone and/or a curved shape.
27. The grinding and/or cutting tool according to claim 26, wherein the surface region for circumferential grinding and/or cutting has a convexly curved shape.
28. The grinding and/or cutting tool according to claim 26, wherein the surface region for circumferential grinding and/or cutting has the conical shape and an angle between surface lines of the surface region and an axis of a cone portion forming the surface region is <3.
29. The grinding and/or cutting tool according to claim 28, wherein the angle is <2.
30. The grinding and/or cutting tool according to claim 16, further comprising a face grinder body, which comprises the surface region for face grinding, and a circumferential grinder and/or cutter body, which comprises the surface region for circumferential grinding and/or cutting.
31. The grinding and/or cutting tool according to claim 30, wherein the face grinder body and/or the circumferential grinder and/or cutter body are configured to be releasably fastened to the grinding and/or cutting tool.
32. The grinding and/or cutting tool according to claim 19, further comprising a main body formed as a grinder and/or cutter in the surface region for circumferential grinding and/or cutting.
33. The grinding and/or cutting tool according to claim 32, wherein at least one of the surface regions for face grinding is formed by an abrasive onlay that is connected to the main body.
34. The grinding and/or cutting tool according to claim 33, wherein the abrasive onlay is an abrasive sheet, an abrasive paper, an abrasive band or an abrasive film.
35. The grinding and/or cutting tool according to claim 33, wherein the abrasive onlay is firmly connected to the main body by adhesive bonding.
36. The grinding and/or cutting tool according to claim 35, wherein the adhesive onlay is a composite material that has a backing fabric.
37. The grinding and/or cutting tool according to claim 35, wherein the main body has at least one recess into which the abrasive onlay is placed.
38. The grinding and/or cutting tool according to claim 37, wherein the recess is arranged at a distance from the surface region for circumferential grinding and/or cutting.
39. The grinding and/or cutting tool according to claim 33, wherein the main body has steps for receiving portions of the abrasive onlay that form the abrasive onlay, wherein the steps are formed in succession in a radial direction and/or in a circumferential direction of the grinding and/or cutting tool.
40. The grinding and/or cutting tool according to claim 39, wherein edges of the steps are arranged in the radial direction and/or along at least one circular line that is parallel to an edge of the grinding and/or cutting tool.
41. A method for grinding and/or cutting, comprising the step of machining an item with a grinding device that comprises a grinding and/or cutting tool that has a surface region for face grinding and a surface region for circumferential grinding or cutting, wherein the item is machined differently by the surface regions having material properties differing from each other.
Description
[0065] The invention is explained in more detail below on the basis of illustrative embodiments and with reference to the accompanying drawings, which relate to the illustrative embodiments and in which:
[0066] FIGS. 1 to 10 show various grinding and/or cutting tools according to the invention, in each case in different views,
[0067] FIGS. 11 to 12 show the grinding and/or cutting tool from FIG. 8 mounted on a grinding machine during machining of a workpiece,
[0068] FIG. 13 shows the grinding and/or cutting tool from FIG. 8 mounted on a further grinding machine during machining of a workpiece,
[0069] FIG. 14 shows a further grinding and/or cutting tool according to the invention mounted on a grinding machine, and
[0070] FIGS. 15 to 27 show further various grinding and/or cutting tools according to the invention, in each case in section and in a perspective view.
[0071] FIG. 1 shows a grinding and cutting tool 1 according to the invention, which is substantially disk-shaped. It comprises a sleeve 11 with which it can be fastened to a grinding machine, for example an angle grinder, and a main body 6 which is connected rigidly to the sleeve 11 and which is formed from a substance combination that comprises a binder with added abrasive. Abrasive onlays 7, 7, which form surface regions 2, 4 for face grinding, are arranged on mutually opposite main surfaces of the main body 6. A surface region 3 for cutting at an outer edge 5 of the grinding and cutting tool 1 is formed by the main body 6. The sleeve 11 is of such a shape that it can be fastened with both sides to the grinding machine.
[0072] The substance combination from which the main body 6 is formed is suitable for introducing a cut, with the surface region 3 of the cutting and grinding tool 1, into a workpiece in order to cut the latter. The abrasive onlays 7, 7 are provided to be used for face grinding. Provision can be made that the two abrasive onlays 7, 7 are formed from the same material or from different materials. In the first case, the lifetime of the grinding and cutting tool 1 increases by comparison with a grinding tool that can be used only with one side, since the grinding and cutting tool 1 can be turned on a grinding machine and fastened the other way round, if one of the surface regions 2, 4 is worn. In the second case, different grinding effects on a workpiece that is to be machined can be achieved with the different surface regions 2, 4.
[0073] Reference is now made to FIGS. 2 to 12, where identical parts or parts that have an identical action are designated by the same reference number as in FIG. 1, with a letter being added in each case to the respective reference number.
[0074] A grinding and cutting tool 1a shown in FIG. 2 has substantially the shape of a grinding plate. A main body 6a of the grinding and cutting tool 1a is connected to a sleeve 11a for fastening to a grinding machine and has on its surface a recess 8 into which an abrasive onlay 7a is inserted, which forms a surface region 2a for face grinding. The surface region 2a for face grinding has the shape of a lateral surface of a cone. A radially outer edge of the main body 6a forms a surface region 3a for cutting. With the grinding and cutting tool 1, it is possible, on the one hand, to carry out face grinding by means of the conical surface region 2a and to cut material of a workpiece by means of the surface region 3a.
[0075] FIG. 3 shows a further grinding or cutting tool 1b, which differs from the tool according to FIG. 2 mainly in that a surface region 2b for face grinding, formed by an abrasive onlay 7b, has a convexly curved shape. Material can be cut using a surface region 3b at the radial outer edge of a main body 6b.
[0076] A further grinding and cutting tool 1c, shown in FIG. 4, differs from the tool according to FIG. 3 particularly in that a main body 6c has two different material regions. In contrast to the illustrative embodiments described above, the main body 6c has abrasive material only in an edge region 20, which forms a surface region 3c for grinding and/or cutting, and it is free of the abrasive material outside the edge region 20. It is advantageous, for the production of the main body 6c, that the comparatively expensive abrasive material needs to be provided only in the edge region 20. For this reason, the main body 6c and therefore the entire grinding and cutting tool can be produced more cost-effectively.
[0077] FIG. 5 shows a further grinding and cutting tool 1d according to the invention, which has substantially the shape of a grinding plate. It comprises a main body 6d formed from a substance combination comprising a binder with added abrasive. An outer main surface of the main body 6d is designed as a surface region 4d for face grinding. Moreover, an edge of the main body 6d forms a surface region 3d for cutting. Arranged on the other main surface of the main body 6d is a support body 15 to which a grinding onlay 7d is fastened which forms a surface region 2d for face grinding. The support body 15 is shaped in such a way that the surface region 2d has the shape of a lateral surface of a cone. The grinding and cutting tool 1d can be used in three different functions, namely with the surface region 2d for face grinding with a conical surface shape, with the surface region 4d for face grinding for grinding with a plane surface shape, and with the surface region 3d for cutting a workpiece.
[0078] A cutting and grinding tool 1e shown in FIG. 6 comprises a main body 6e made from a substance combination of binder and abrasive. The main body 6e has a radially outer edge that is thicker compared to an inner region of the main body 6e. The outer edge forms a surface region 3e by means of which a workpiece can be cut or can be machined by circumferential grinding. Inward from the edge region 20e, support bodies 15e, 16e are arranged on both sides of the main body 6e, said support bodies 15e, 16e being provided with recesses 8e, 8e for receiving abrasive onlays 7e, 7e that form surface regions 2e, 4e for face grinding. The top side and the underside of the edge region 20e, the support bodies 15e, 16e and the onlays 7e, 7e are adapted in size to one another in such a way that the respective surfaces of the edge region 20e and of the abrasive onlays 7e, 7e are arranged at the same height, such that no step is formed there. The support body 15e is shaped in such a way that the surface region 2e has the shape of a lateral surface of a cone. The support body 16 is of such a shape that the surface region 4e is convexly curved. The grinding and cutting tool 1e also allows a workpiece to be machined in different ways with the different surface regions 2e, 3e, 4e.
[0079] A further grinding and cutting tool if, shown in FIG. 7, differs from the tool according to FIG. 6 particularly in that abrasive onlays 7f, 7f are also arranged on a surface region 20f at the edge of a main body 6f. In this way, larger grinding surfaces are created on both surface regions 2f, 4f for face grinding.
[0080] FIG. 21 shows a further grinding and/or cutting tool 1x, having a main body 6x whose edge forms a surface region 3x for circumferential grinding, and having a support body 5 which can fastened releasably to the grinding and/or cutting tool 1x or can be connected releasably to the main body 6x. An abrasive onlay 7x is fastened, e.g. by adhesive bonding, to the support body 5. The main body 6x is provided with a circular groove 45 into which protrude the outer edge of the support body 5 and the abrasive onlay 7x. In the present example, the grinding and/or cutting tool 1x comprises a shaft 46 with an outer thread, at which the main body 6x and the support body 5 can be braced against each other by means of a clamping nut 47. Alternatively, the releasable connection could be formed by the support body 5 being screwed directly onto the main body 6x.
[0081] A grinding and/or cutting tool 1x, shown in FIG. 22, differs from the tool according to FIG. 21 in that three circular grooves 45x, 45x, 45x are formed coaxially in a main body 6x. Support bodies 5x, 5x, 5x of different diameter can be attached to the main body 6x. Advantageously, the grinding and/or cutting tool 1x can also be used further when the diameter of the main body 6x decreases through the removal of material during circumferential grinding or cutting. As soon as the diameter is reduced to such an extent that its radially outer edge lies in the radial direction at the same height as the radially outer edge of the support body 5x, 5x, the respective support body 5x, 5x is detached and machining is continued with a smaller one. It is conceivable, as shown in FIG. 22, to arrange three different support bodies 5x, 5x, 5x on the main body 6x at the same time. However, in the preferred embodiment of the invention, only one of the support bodies 5x, 5x, 5x at a time is fastened to the main body 6x, in contrast to what is shown in FIG. 22. In a first phase, the grinding and/or cutting tool 1x is used with the support body 5x of the greatest diameter. As soon as the main body 6x has become worn by circumferential grinding or cutting to such an extent that its diameter is the same as or smaller than that of the support body 5x, the support body 5x is taken off and the support body 5x is attached. Handled in the same way, the grinding and/or cutting tool 1x can also be used for circumferential grinding with the support body 5x until the diameter of the main body 6x has reduced to such an extent that it is the same as or smaller than that of the support body 5x.
[0082] A further grinding tool 1g according to the invention, shown in FIG. 8, is similar in design to the grinding and cutting tool 1a according to FIG. 2. However, it differs from the grinding and cutting tool according to FIG. 2 in that an edge of a main body 6g, which forms a surface region 3g for circumferential grinding, is substantially thicker than the surface region 3a for cutting of the tool according to FIG. 2. A recess 8g for receiving an abrasive onlay 7g is formed at a distance from a radially outer edge of the main body 6g, such that a surface region 3g for circumferential grinding is broader than the region for cutting 3a of the tool according to FIG. 2. As FIG. 8a shows, the abrasive onlay 7g has cutouts 9, which are arranged in the radial direction and at a distance from one another, and the main body 6g has webs 10 which protrude in the radial direction from the edge and have a shape matching the cutouts 9. Advantageously, by virtue of this configuration, the abrasive onlay 7g is better fixed to the main body 6 and additionally supported in the circumferential direction, and its radially outer edge is protected from coming loose during working with the grinding tool 1a, since the edge of the main body 6g protrudes over the end of the abrasive onlay 7g and engages around the latter. Moreover, by virtue of the predefined position, the abrasive onlay 7g can be more easily fastened to the main body 6g.
[0083] A further grinding tool 1h, shown in FIG. 9, differs from the tool according to FIG. 8 in that a support body 15h, which supports an abrasive onlay 7h, is arranged on a main body 6h. Here too, an edge region, which forms a surface region 3h for circumferential grinding, encloses the abrasive onlay 7h and the support body 15h. The main body 6h, formed from a substance combination of binder and abrasive, is plane on an underside, such that the underside can be used as a surface region 4h for face grinding.
[0084] FIG. 10 shows a variant of a grinding tool 1i which, in principle, is configured in the same way as the grinding tool 1g according to FIG. 9, but in which a surface region 2i for face grinding has a concave curvature.
[0085] FIG. 15 shows a further conical grinding and cutting tool 1p according to the invention, having a main body 6b and, arranged on the cutting body 6b, abrasive onlays 7p, 7p, 7p. On the main body 6p, steps 40, 41, 42 are formed which ascend successively from the outside inward in the radial direction, wherein edges of the steps 40, 41, 42 are circular. Starting from the uppermost step 40, rectilinear webs 10p are formed in the radial direction and protrude upward from the steps 41, 42. Moreover, starting from the step 41, webs 10p are formed which protrude upward from the step 42. To be able to arrange the abrasive onlays 7p, 7p, 7p on the main body, the abrasive onlays 7p, 7p are ring-shaped, wherein their external diameter corresponds to the external diameter of the main body 6p, and their internal diameter is chosen such that the abrasive onlays 7p, 7p, 7p each bear on the outer side of the collar 17 or the outer edges of the steps 40, 41. In addition, the abrasive onlays 7p, 7p are provided with recesses which each correspond to the shapes of the webs 10p, 10p, such that the abrasive onlays can each bear on the steps 40, 41, 42 by means of the webs 10p, 10p engaging in the recesses.
[0086] The grinding and cutting tool 1p advantageously has the three abrasive onlays 7p, 7p, 7p in an outer annular region that is normally exposed to particularly strong stresses, and the tool can therefore be used for a particularly long time. The main body 6p is formed from a substance combination of binder and abrasive, and its edge 3p can therefore be used for circumferential grinding or for cutting.
[0087] FIG. 15e shows a further grinding and cutting tool 1q according to the invention, which differs from the grinding and cutting tool 1p in that a main body 6q is plane on a side provided to receive abrasive onlays 7q, 7q, 7q and can thus be used on the plane side in another function for grinding.
[0088] FIG. 16 shows a further grinding and cutting tool 1r according to the invention, which differs from the tool according to FIG. 15 particularly in that a surface of a main body 6r has a convex shape.
[0089] FIG. 16c shows a grinding and cutting means 1s whose main body 6s is plane on one side, i.e. a side directed away from the side provided to receive abrasive onlays 7s. Here too, different grinding effects can advantageously be achieved with the different sides.
[0090] A further grinding and cutting tool 1r according to the invention is shown in FIG. 24. It differs from the tools according to FIGS. 15 and 16 particularly in that a main body 6r is disk-shaped and, at its radially outer edge, has a collar-shaped projection that forms a surface region 3r for circumferential grinding. The grinding and cutting tool 1r moreover comprises a support body 5r which has a shape similar to the main body 6r from FIG. 16. The main body 6r and the support body 5r can be connected to each other by means of a shaft 46r and a clamping nut 47r. Advantageously, the main body 6r or the support body 5r can be replaced when it becomes worn.
[0091] In a further grinding and cutting tool it according to the invention, shown in FIG. 17, abrasive onlays 7t are arranged in a fan shape on a main body 3t.
[0092] The main body 6t has, at its outer edge, a collar-shaped projection, which forms an edge 3t for circumferential grinding. A ring-shaped surface for receiving abrasive onlays 7t is formed between the collar-shaped projection and an inner overhang 17t of the main body 6t. The abrasive onlays 7t have a narrower region 45 which is of such a breadth that they fit on the main body 6t between the overhang 17t and the outer edge 3t and can be secured there. With lateral projections 46, 47, the abrasive onlays can be placed onto the outer edge 3t and the inner overhang 17t. Apart from the portions with which the abrasive onlays 7t are placed directly onto the main body and are secured there, the abrasive onlays 7t lie loosely on one another.
[0093] As FIG. 17d shows in particular, the main body 6t has a convex curvature in the region between the outer edge 3t and the overhang 17t.
[0094] A grinding and cutting tool 1u, shown in FIG. 18, differs from the tool according to FIG. 17 in that a main body 6u has a plane shape. Moreover, in a region where they are securely bonded to the main body 6u between an outer edge 3u and an overhang 17u, abrasive onlays 7u are provided with steps 38, 39 with which they can be securely bonded to the edge 3u or to the overhang 17u.
[0095] FIG. 19 shows a further grinding and cutting tool 1v according to the invention, which is formed a main body 6v and a support body 5v that can be fitted one into the other. At an edge 3v of the main body 6v and in the circumferential direction, steps 43 are formed in the circumferential direction 43 and on the main body 6v and the support body 5v, which steps 43 are provided to receive abrasive onlays 7v that are to be placed in a suitable position in a fan shape on the main body 6v and the support body 5v. When the main body 6v and the support body 5 are arranged correctly on each other, the steps are formed continuously in the radial direction as far as the outer edge of the main body 6v.
[0096] The physical separation of the main body 6v and the support body 5v makes it possible to produce the main body 6v and thus the edge 3v from a material with added abrasive and to produce the support body 5v from plastic, which is free of the abrasive and is thus more cost-effective. In addition, there is the possibility of detaching the main body 6v or the support body 5v from the grinding and cutting tool 1v and replacing it when it becomes worn. Advantageously, the tool can continue to be used cost-effectively when the only one of the bodies is worn and the other can continue to be used.
[0097] The steps 43, 43 formed in the circumferential direction make it possible to arrange and, if appropriate, adhesively bond the abrasive onlays 7v on the main body 6v and the support body 5v in such a position that, when placed on one another, they do not need to have a curved arrangement. Advantageously, this makes it possible to form several layers of the abrasive onlays on the grinding and cutting tool 1v, with particularly good binding to the main body 6v and if appropriate the support body 5v.
[0098] FIG. 20 shows a further grinding and cutting tool 1w according to the invention, which differs from the tool according to FIG. 19 particularly in that it has a substantially plane shape. Moreover, a support ring 44 is formed underneath a lower part 6w of a main body.
[0099] A further grinding and cutting tool 1y according to the invention, shown in FIG. 23, differs from the tools according to FIGS. 17 to 20 particularly in that a surface region 3y for circumferential grinding, formed on a main body 6y, has a collar-shaped projection. The projection is more or less perpendicular to a surface portion of the main body 6y on which a support body 5y is arranged on which the abrasive onlays 7y are fastened by adhesive bonding. The projection is provided in such a position and has such a height that it encloses the abrasive onlays 7y in a pot shape. Moreover, the main body 6y and the support body 5y can be fastened releasably to the grinding and cutting tool 1y, such that they can each be taken off and replaced when they become worn. The main body 6y and the support body 6y can be braced against each other on a shaft 46y by means of a clamping screw 47y.
[0100] FIG. 11 shows the use of a further grinding and cutting tool 1j, which is basically of the same configuration as the grinding tool 1g according to FIG. 8 but which, at its edge forming a surface region 3g for cutting, has a smaller thickness than the grinding tool 1g and is therefore particularly suitable for cutting. The grinding and cutting tool 1j is fastened on an angle grinder 18 and is used to cut a bolt 19, which are fastened to a metal plate 20 and protrude from the latter, and to grind the cut surface directly after the cutting work. For this purpose, as is shown in FIG. 11a, the grinding machine 18 is held in such a way that a surface region 2j for face grinding lies along a line on the metal plate 20 and the grinding and cutting tool 1j is guided, under rotation, in the direction of the bolts 19, such that an edge of the grinding and cutting tool 1j, which forms a surface region 3j for cutting, cuts the bolt 19 from the metal plate 20. By means of the surface region 2j, the metal plate can be ground directly thereafter in the cut region.
[0101] FIG. 11c shows a support bracket 21 that can be fastened to the angle grinder 18. The support bracket 21 has a roller 22 with which the angle grinder can be arranged in a manner stable against tilting when the grinding and cutting tool 1j is placed on a substrate. In order to machine the metal plate 20 or the bolts 19, the angle grinder can now be supported on the support bracket and is automatically held, with respect to the metal plate 20, at the angle setting in which the latter is to be ground with the surface region 2j.
[0102] A further combination of a grinding machine 18n, which is provided with a grinding and cutting tool 1n, and of a support bracket 21n is shown in FIG. 12. It differs from the one according to FIG. 11 in that a guide mechanism 33 is arranged on a part 36 of a housing of the grinding machine 18n, which guide mechanism 33 comprises two webs 34, 35 arranged at a distance from each other. The webs 34, 35 are arranged at such a distance from each other that the bolt 19 can be pushed in between them. Advantageously, the webs 34, 35 support themselves on the bolt 19 during the cutting off of the bolt 19. In this way, during the cutting of the bolts 19, the grinding machine 18n can be much more easily held in the correct position for cutting the bolt 19, preventing it from sliding sideways from the bolt 19 during the cutting work.
[0103] In the embodiment of the guide mechanism 33p shown in FIG. 12d, an attachment 37 is provided at the end of the webs 34p, 35p, which attachment 37 is supported on the metal plate 20 during the cutting or grinding work and thus forms an additional guide.
[0104] FIG. 13 shows the use of a further grinding tool 1k, which is basically of the same configuration as the grinding tool 1j according to FIG. 11 and sits on a grinding machine 18k. The grinding machine 18k is fastened to a holding mechanism 23, which is arranged on a pipe 24 of circular cross section and holds the grinding machine 18k in a position for machining the edge 25.
[0105] The holding mechanism 23 comprises a mechanism 26 for fastening it to the pipe 24, which mechanism 26 has three struts 27 which can each comprise a clampable threaded spindle and can be arranged with clamping on the inner side of the pipe 24. A holding unit 28 of the holding mechanism 23, to which the grinding machine 18k is fastened, is connected rotatably to the fastening mechanism 26 via a connection unit 29 that comprises a pivot joint. The holding unit 28 is connected to the connection unit 29 via bars 30 and is displaceable, in the longitudinal direction of the bars 30, with respect to the connection unit 29. The holding unit 28 comprises a roller 31 which bears on the inner side of the pipe 24 and thus secures the position of the grinding machine 18k or of the grinding tool 1k relative to the pipe 24 in the radial direction at the edge 25. The holding unit 28 is pressed away from the connection mechanism 29 in the longitudinal direction of the bars 30 by means of a spring 32, such that the roller 31 at all times bears with stress on the inner wall of the pipe when the entirety of the grinding machine 18k and holding mechanism 23 is arranged on the pipe 24.
[0106] In order to machine the edge 25 of the pipe 24, the grinding machine 18, having been fastened to the pipe 24 by means of the holding mechanism 23 as explained above and shown in FIG. 13, is first of all arranged such that it bears with the grinding tool 1k on the region of the edge 24 that is to be machined. The grinding machine 18k is then switched on, and the grinding tool 1k is set in rotation. The grinding machine 18k is now turned around the fastening mechanism 29 and thus around the pipe axis (as shown by the arrow D in FIG. 13) and is thereby moved along the pipe edge 24. The holding unit 28 is pressed by the spring 32 away from the fastening mechanism 26 toward an inner wall of the pipe 24, and the roller 31 is thereby pressed against the inner wall of the pipe. Since the position of the grinding machine 18k is fixed with respect to the roller 31, the grinding tool 1k is at all times in the intended machining position during the movement along the edge 25. The depicted arrangement of the grinding tool 1k is particularly suitable for forming a recess at the pipe edge, for example for forming a so-called tulip shape, which is advantageous for welding the pipe 24.
[0107] Since, during the machining of the pipe edge, the grinding tool 1k is subjected to particularly strong mechanical loads in its surface region 3k for circumferential grinding and in the region of the edge between the surface regions 2k and 3k and is also stressed by heating, a main body 6k of the grinding tool 1k that forms the surface region 3k for circumferential grinding has been provided with a particularly wear-resistant abrasive, and a particularly wear-resistant binder has been chosen. In order to form the surface region 2k for face grinding, an abrasive onlay 7k has been chosen that can achieve comparatively greater removal. Compared to the main body 6k, it can have larger abrasive particles. Moreover, the abrasive particles of the abrasive onlay 7k can be bound to a comparatively lesser extent in binder and can thus lie freer at the surface, so as to bring about greater removal of material. On account of the lesser stress, the binder of the abrasive onlay 7k can be provided to be less resistant to wear and therefore more cost-effective.
[0108] The grinding and cutting tools 1j, 1j shown in cross section in FIGS. 26 and 27 are also suitable in particular for the uses shown in FIGS. 11 to 13. The grinding and cutting tool 1j from FIG. 26 has, as main body 6j, a diamond cutting disk, while the grinding and cutting tool 1j from FIG. 26 has, as main body 6j, a resin-bonded cutting disk. The main body 6j, 6j has a pot-shaped inner portion into which an abrasive body 7j, 7j can be inserted. A disk 48, 48 is arranged as spacer between the main body 6j, 6j and the abrasive body 7j, 7j. Through the use of spacer disks 48, 48 of different thickness, the position of the abrasive bodies 7j, 7j in relation to the main body 6j, 6j can be changed.
[0109] A grinding and cutting tool 1m, shown in FIG. 14, differs from the grinding and/or cutting tools explained above particularly in that its edge both has two surface regions 3m, 3m for circumferential grinding and also a surface region 3m for cutting. As has been explained above for the other grinding and/or cutting tools, the surface regions 3m, 3m are each formed on respective main bodies 6m, 6m, which have a substance combination of a binder with added abrasive. A cutting disk 6m, likewise formed from a combination of binder and abrasive, is arranged between the main bodies 6m, 6m and has a greater diameter than the main bodies 6m, 6m and therefore also protrudes outward.
[0110] An advantageous use of the grinding and cutting tool 1m is that a workpiece can first of all be cut by means of the surface region 3m, and then an edge formed by the cutting process can be machined directly by circumferential grinding by means of the surface regions 3m, 3m or the surface regions 2m, 2m for face grinding. Such a use is suitable in particular for the machining of pipes.
[0111] FIG. 25 shows a further grinding tool 1z according to the invention, having a main body 6z with a conical shape. Steps ascending in the circumferential direction are formed on a lateral surface of the main body 6z. A respective abrasive onlay 7z is bonded to each of the steps. At a lower edge of the main body 6z, a circumferential web 2z is formed, of which the underside can be used as a grinding surface for face grinding.
[0112] In a further illustrative embodiment, not shown here, the main body 6z according to FIG. 25 has a cylindrical shape instead of a conical one.
[0113] In a further embodiment of the invention, not shown here, a grinding tool has the same outer shape as the grinding tool 1z from FIG. 25 or has a cylindrical shape, but is provided with a support body which carries the abrasive onlays 7z and is connected releasably to a main body to which the support body can be fastened. The main body is formed and shaped from such a material that its lower side can be used as a grinding surface for face grinding. Advantageously, the support body or the main body can be replaced if it becomes worn.
[0114] The surface regions of the above-described grinding and/or cutting tools can differ from one another in terms of their removal properties, particularly by the fact that they have different material properties. The different material properties can be provided by the fact that the surface regions have different abrasives. The abrasives can differ in terms of the substances of the abrasive particles, e.g. corundum, quartz, pumice, diamond, silicon carbide and/or cubic boron nitride. Moreover, the surface regions can differ from one another in terms of different abrasive particle shapes and sizes, particle scatter, granules, hardness, structure, porosity, strengthening materials (fibers, in particular glass or carbon fibers), support materials and/or binders.
