Abstract
A method for producing a preliminary material for a cutting tool and such a preliminary member, for example a preliminary material for a saw blade, a saw band, a cutting line, a punching knife, or a blade, wherein at least one first particulate cutting-edge material is applied to a planar carrier, the first particulate cutting-edge material is welded to the planar carrier, and the planar carrier is separated substantially along the weld joint thus produced.
Claims
1-15. (canceled)
16. A method for producing a preliminary material for a machining tool, or a preliminary material for a saw blade, a saw band, a cutting line, a punching knife or a blade, the method comprising: applying at least a first particulate cutting-edge material to a sheet-like base; welding the first particulate cutting-edge material to the sheet-like base; and separating the sheet-like base substantially along the welded connection thus produced.
17. The method as claimed in claim 16, wherein the first particulate cutting-edge material is introduced into a depression cut out on the upper side and/or the underside of the sheet-like base.
18. The method as claimed in claim 17, wherein the sheet-like base is a band of metal or metal alloy.
19. The method as claimed in claim 16, wherein the first particulate cutting-edge material is welded to the sheet-like base such that the sheet-like base and/or the first particulate cutting-edge material is/are at least partially melted and the molten material composite is left to solidify at least partially.
20. The method as claimed in claim 16, wherein the sheet-like base comprises a main body of a base material.
21. The method as claimed in claim 20, wherein the sheet-like base includes in the base material at least one region of a further cutting-edge material, and the first particulate cutting-edge material is applied to the at least one region.
22. The method as claimed in claim 16, wherein, before separating the composite comprising the base and the first cutting-edge material, at least a second particulate cutting-edge material is supplied and melted.
23. The method as claimed in claim 16, wherein the particulate cutting-edge material is supplied in a form of a powder, granules, a paste, or a tilling wire.
24. The method as claimed in claim 16, wherein the cutting-edge material includes metals and/or metal alloys.
25. The method as claimed in claim 16, wherein the cutting-edge material includes metallic hard materials.
26. The method as claimed in claim 16, wherein the sheet-like base and the particulate cutting-edge material are welded to one another by supplying energy by at least one welding device.
27. The method as claimed in claim 16, wherein the particulate cutting-edge material is supplied to both sides of the sheet-like base.
28. A sheet-like preliminary material for producing a machining tool, or a saw blade, a saw band, a cutting line, a punching knife or a blade, obtainable by the method as claimed in claim 16, comprising: a sheet-like base, which includes a main body of a base material, and a cutting-edge region of at least a first cutting-edge material, the sheet-like base and the cutting-edge region being connected to one another by a first alloying zone, wherein the cutting-edge region and the sheet-like base overlap over a cross-sectional length that lies in a range of 0.2-3 times the cross-sectional width of the sheet-like base.
29. A method for producing a preliminary material for a machining tool, or a preliminary material for a saw blade, a saw band, a cutting line, a punching knife or a blade, the method comprising: providing a sheet-like base, which comprises a main body of base material and a cutting-edge region of cutting-edge material; applying at least one particulate cutting-edge material to at least one edge of the cutting-edge region of the sheet-like base; and welding the particulate cutting-edge material to the sheet-like base.
30. A sheet-like preliminary material for producing a machining tool, or a saw blade, a saw band, a cutting line, a punching knife or a blade, obtainable by the method as claimed in claim 21, comprising: a sheet-like base, which includes a main body of a base material, and a cutting-edge region of a cutting-edge material, the cutting-edge region including at least one corner a corner region of at least one other cutting-edge material, wherein the corner region and the cutting-edge region are connected to one another by an alloying zone.
Description
[0037] In the drawings:
[0038] FIG. 1 shows a schematic representation of the production of a welded connection between a sheet-like base and supplied particulate cutting-edge material in the method according to the invention;
[0039] FIG. 2 shows a variant of FIG. 1 in which the sheet-like base has depressions for receiving the particulate cutting-edge material;
[0040] FIG. 3 shows a variant of FIG. 1 in which the sheet-like base is formed as a bimetallic base with a central strip of a different material;
[0041] FIG. 4 shows a variant of FIG. 1 or FIG. 2 in which two particulate cutting-edge materials are supplied;
[0042] FIG. 5 shows the preliminary material according to the invention from FIG. 1 or FIG. 2 after the welded connection has been established;
[0043] FIG. 6 shows the preliminary material according to the invention from FIG. 5 after the flattening of the welded connection;
[0044] FIG. 7 shows the preliminary material according to the invention from FIG. 3 after the welded connection has been established;
[0045] FIG. 8 shows the preliminary material according to the invention from FIG. 7 after the flattening of the welded connection;
[0046] FIG. 9 shows the preliminary material according to the invention from FIG. 4 after the welded connection has been established;
[0047] FIG. 10 shows the preliminary material according to the invention from FIG. 9 after the flattening of the welded connection;
[0048] FIG. 11 shows the preliminary material of FIG. 6 after the separation of the welded connection;
[0049] FIG. 12 shows the preliminary material of FIG. 8 after the separation of the welded connection;
[0050] FIG. 13 shows the preliminary material of FIG. 10 after the separation of the welded connection;
[0051] FIG. 14 shows a schematic representation of the application of a particulate cutting-edge material to the cutting edge of a sheet-like base;
[0052] FIG. 15 shows a variant of the method of FIG. 14 in which particulate cutting-edge material is applied from three directions; and
[0053] FIG. 16 shows the preliminary material according to the invention from FIG. 15 after working on the edge region;
[0054] In FIG. 1, a first embodiment of the method according to the invention for producing a preliminary material for a machining tool, for example a preliminary material for a saw blade, a saw band or a cutting line, is schematically shown by way of example. A sheet-like base 10 can be seen, in the example shown merely comprising a unitary main body 11 of a base material. To provide a better overview, in the example shown the sheet-like base is shown as a short portion. Preferably, however, it is a continuous band, which is for example unwound from spools, which are likewise not shown here. The sheet-like base 10 has an upper side 13 and an underside 14, which in the example shown are flat. By means of a welding head 15 of a welding device that is not shown any further, a first particulate cutting-edge material 16 is applied to the upper side 13 of the sheet-like base 10 and melted by means of a laser beam 17, so that the base 10 and the particulate cutting-edge material 16 can be welded to one another. In the example shown, the welding head 15 of the welding device has for this purpose an annular nozzle 18, to which the particulate cutting-edge material 16 is supplied by means of lines 19, 20. However, any other kind of nozzle may also be used. The annular nozzle 18 shown produces a conical jet of the particulate cutting-edge material 16, which is directed onto the upper side 13 of the base. The laser beam 17 is made to pass through the center of the welding head 15 and the center of the conical jet of the cutting-edge material 16 and is focused onto a region 21 in which the cutting-edge material impinges on the surface of the base 10. In this region, the welding process takes place. Depending on the materials used, the particulate cutting-edge material 16 and/or a matrix material supplied together with the cutting-edge material and/or the base material in the welding region 21 are at least partially melted, so that a welded connection 22 is created.
[0055] The sheet-like base, i.e. in the example shown the continuous band, is moved under the stationary welding head 15 along the arrow 23.
[0056] FIG. 2 shows a variant of the embodiment of FIG. 1 in which the sheet-like base has depressions 24, 25 for receiving the particulate cutting-edge material. Elements that correspond to the elements already described in conjunction with FIG. 1 are designated by the same reference numerals. In the case of this variant, the sheet-like base 10 has on its upper side 13 a rounded depression 24 and on its underside a rounded depression 25. The depressions 24, 25 on the one hand reduce the weld ridge of the welded connection 22 beyond the surface of the sheet-like base 10, so that the re-working effort, and in particular the loss of cutting-edge material during the re-working, is reduced. On the other hand, the thickness of the base material 12 in the welding region 21 is reduced, so that, as explained in more detail further below, an edge region that substantially consists of cutting-edge material 16 is created after separating the welded connection.
[0057] FIG. 3 shows a variant of the embodiment of FIG. 1 in which the sheet-like base 10 is formed as a bimetallic base. The sheet-like base 10 has a main body 11 of base material 12, which is divided into two side strips 10a, 10b. The two side strips 10a, 10b are connected to one another by a central strip 10c of a more resistant material, for example of high-speed steel 26. Such a variant of the base 10 may be produced for example by the method known from the applicant's WO 2006/000256 A1. By analogy with the embodiment of FIG. 1, the base 10 is shown as flat. It goes without saying that the base 10 may be provided in the region of the central strip 10c with upper and/or lower depressions, as described in conjunction with FIG. 2.
[0058] In the variant of FIG. 4, various modifications of the embodiment of FIG. 1 or of FIG. 2 are shown. However, the invention is not restricted to the combination of these modifications that is shown, but instead each of the modifications described below may be realized individually or in combination with the variant described in FIG. 3. Thus, a sheet-like base 10 which, by analogy with the variant of FIG. 2, is provided with two depressions 24, 25 is used in the variant of FIG. 4. In the variant shown here, however, the depressions have an angular cross-sectional profile. Furthermore, in the variant of FIG. 4, two welding heads 15a, 15b arranged one behind the other are used instead of one welding head 15. By analogy with the procedure of FIG. 1, the welding head 15a guides a first cutting-edge material 16a into the upper recess 24 and produces a welded connection 22 by means of the laser 17a. With the welding device 15b, a further cutting-edge material 16b may be applied and welded to the first cutting-edge material to produce a multilayered cutting-edge region. If no further cutting-edge material has to be applied, it is also possible to use the laser device 17b of the second welding device 15b, or a similar heat source, for heat-treating the welded connection 22, in order to reduce stresses in the welded connection.
[0059] In the representations of FIGS. 1 to 4, particulate cutting-edge material is applied from the upper side 13 to the the sheet-like base 10. Usually, however, a supply of the cutting-edge material from the upper side 13 and the underside 14 of the sheet-like bases, simultaneously or successively, is preferred. For a supply that takes place successively, the arrangement of sheet-like bases 10 may for example be led or twisted over a deflecting roller (not shown), so that the underside 14 shown in FIGS. 1 to 4 is subsequently upwardly directed and the upper side 13 with the already produced welded connection 22 is downwardly directed.
[0060] In FIGS. 5 and 6, the result of the welding process of FIG. 1 or of FIG. 2 is shown, cutting-edge material 16 having been introduced both into the upper depression 24 and into the lower depression 25, so that an upper welded connection 22 and a lower welded connection 27 are formed. In the region of the bottom of the depressions 24, 25, an upper alloying zone 28 and a lower alloying zone 29 are respectively created between the base material and the supplied particulate cutting-edge material 16 as a result of melting of the materials by the laser beam 17. It can be seen that the welded connections 22, 27, which substantially consist of the particulate cutting-edge material 16 supplied and melted, protrude beyond the upper side 13 or underside 14 of the sheet-like base 10, in the form of a weld elevation. In such a case, the welded connections are preferably also flattened, so that a flat composite is obtained, as shown in FIG. 6. Before or as an alternative to the flattening, the weld elevations may possibly also be ground away. In addition or as an alternative to the flattening, the welded connections 22, 27 may also be worked by means of a flattening operation. In this way, a preliminary material that can be processed into special tooth geometries, for example trapezoidal teeth, with less effort than the methods known from the prior art can be produced.
[0061] The base 10 is subsequently separated substantially along the welded connections 22, for example along the separating line 30 shown in FIG. 6. After the separation, and possibly further working steps, the preliminary material according to the invention is obtained in the form of two sheet-like bases, advantageously bands, with in each case an edge region that consists substantially of a cutting-edge material (compare FIGS. 11 and the associated descriptions further below). The preliminary material according to the invention may be for example two bimetallic bands, which can subsequently be further processed into a machining tool by introducing teeth into the edge region. In the example shown, the separating line 30 is a straight center line through the welded connections 22, 27. However, the separating line may also have a more complicated form and for example be approximated to the desired later form of the teeth. The separation of the sheet-like base into two halves is preferably already carried out during the production of the preliminary material according to the invention, so that two bands each with a cutting edge are created.
[0062] In FIGS. 7 and 8, the result of the welding process of FIG. 3 is shown in a way similar to in FIGS. 5 and 6. The particulate cutting-edge material 16 has been applied here to the central strip 10c, preferably consisting of high-speed steel 26, of the base 10 and welded to the high-speed steel. It can be seen that, although the surface of the high-speed steel 26 was flat, the laser welding ensures that the welded connection can penetrate a little into the flat base. Again, an upper welded connection 22 and a lower welded connection 27 with alloying zones 28, 29 have been formed. In FIG. 8, the sheet-like base 10 with the welded connections 22, 27 after the flattening is shown. Here too the base 10 is separated substantially along the welded connections 22, for example along the separating line 30 shown in FIG. 8. A separated half of the base is shown in FIG. 12.
[0063] In FIGS. 9 and 10, the result of the welding process of FIG. 4 is shown in a way similar to in FIGS. 5 and 6. Here, first a first particulate cutting-edge material 16a was applied and welded to the base material 12 of the sheet-like base 10, so that a first alloying zone 28a was formed between the base material 12 and the first cutting-edge material 16a. A second particulate cutting-edge material 16b was applied to the welded-in cutting-edge material 16a and welded to it while forming an alloying zone 28b, so that a two-layered welding connection 22 is formed. Correspondingly, two layers of particulate cutting-edge material 16a, 16b were applied to the underside 14 of the sheet-like base 10 to form the welded connection 27. In FIG. 10, the sheet-like base 10 with the welded connections 22, 27 after the flattening is shown. Here too the base 10 is separated substantially along the welded connections 22, for example along the separating line 30 shown in FIG. 8. A separated half of the base is shown in FIG. 13.
[0064] In FIGS. 11, 12 and 13, one half of the preliminary materials according to the invention that is created after the cut shown in FIGS. 6, 8 and 10 is in each case shown in cross section.
[0065] It can be seen in FIG. 11 that, after the cut along the separating line 30, a cut surface 31 has been created in each of the welded connections 22, 27. In the case of the variant of FIG. 11, base material 12 reaches into the cut surface 31. To the side of that there are cutting-edge regions 32, 33 of the originally particulate cutting-edge material 16. If desired, this base material may be milled out by introducing a groove (not shown), for example a wedge-shaped groove, into the cut surface 31, so that during the later further processing by the saw manufacturer there is no longer any base material in the region of the tips of the teeth. It is characteristic of the method according to the invention, in which the cutting-edge material 16 is applied in the form of powder to the base, that, by contrast with the classic bimetallic band of HSS edge wire, a substantially horizontal weld seam/alloying zone is not created in the cross section of the finished band where the base material 12 and the cutting-edge material 16 go over into one another. Rather, the cutting-edge regions 32, 33 of cutting-edge material 16 reach around a core zone 34 of base material 12. On account of the overlapping of cutting-edge regions 32, 33 of cutting-edge material 16 and base material 12 of the sheet-like base 10, the alloying zones 28, 29 typically do not run horizontally along the height of the finished sheet-like preliminary material as in the case of the classic bimetallic band. The cutting-edge regions 32, 33 of cutting-edge material 16 and the sheet-like base 10 of base material 12 typically overlap in the edge region along the height of the cross section over a length I, which corresponds approximately to 0.2 to 3 times the width b of the sheet-like base 10 in the cross section. In this way, a particularly stable cutting edge is provided.
[0066] FIG. 12 shows a view corresponding to the view of FIG. 11 of a preliminary material according to the invention that is obtained after separating the base 10 of FIGS. 7 and 8 along the separating line 30. In comparison with FIG. 11, the multiphase structure of the cutting-edge regions 32, 33 of the preliminary material according to the invention can be clearly seen, also reflected in the cut surface 31. Since the sheet-like base 10 already had originally a main body with strips 10a, 10b of base material 12 and a central strip 10c of a further cutting-edge material 26, the originally particulate cutting-edge material 16, applied by the method according to the invention, already represents the second layer 35, 36 of cutting-edge material. The alloying zones 28, 29 produced by the method according to the invention accordingly run between the cutting-edge material 26 of the sheet-like base 10 and the welded-on, originally particulate cutting-edge material 16. On the teeth of the machining tool that are later fashioned, the second layers 35, 36 of the cutting-edge regions 32, 33 of the finished preliminary material of FIG. 12 accordingly form additionally strengthened corner regions if a still more resistant material than the cutting-edge material 26 is used as the cutting-edge material 16.
[0067] FIG. 13 shows a view corresponding to the view of FIG. 11 of a preliminary material according to the invention that is obtained after separating the base 10 of FIGS. 9 and 10 along the separating line 30. Here, the cutting edge regions 32, 33 are of a multilayered structure. On the separated surface there can be seen a central strip of base material 12, which is separated by an alloying zone 28a, 29a from the first cutting-edge material 16a, which in turn is separated by an alloying zone 28b, 29b from the second cutting-edge material 16b. The preliminary material of FIG. 13 is also suitable in particular for producing saw teeth with strengthened corner regions.
[0068] In FIGS. 14 to 16, an alternative method for producing a preliminary material for a bimetal band with strengthened corners is described. According to FIG. 14, a sheet-like base 10, which comprises a main body of base material 12 and a cutting edge region 37 of cutting-edge material 26, is provided. With two welding heads 15a, 15b, particulate cutting-edge material 16a, 16b is applied to the corners of the cutting-edge region 37 of cutting-edge material 26 of the sheet-like base 10 and welded to the sheet-like base by means of the laser beams 17a, 17b. In the examples shown, the base 10 again consists of band material and during the welding process is moved through under the welding heads along the arrow 23. The cutting-edge region 37 of the sheet-like base 10 may have been produced by the method according to the invention from a first particulate cutting-edge material or it may consist of a further cutting-edge material, which has for example been welded onto the main body as edge wire. According to the variant of FIG. 15, the particulate cutting-edge material is applied not only to the corners of the cutting-edge region 37 of the sheet-like base 10, but also centrally onto the end face of the cutting-edge region 36 of the base 10 as a particle jet 16C by means of a third welding head 15c. With this variant, not only the production of corners with particularly great wear resistance and cutting strength is made possible, but the entire region of the tooth tip has a strengthened tip region 38 with particularly great wear resistance and cutting strength. The particulate cutting-edge materials 16a, 16b, 16c may be the same or different. If the cutting-edge materials 16a, 16b, 16c are the same cutting-edge material 16, the preliminary material shown in FIG. 16 is created, with a base 10 that has a main body of base material 12 and a cutting-edge region 37 of cutting-edge material 26. The tip region 38, which has been applied by the method according to the invention, consists of the originally particulate cutting-edge material 16.
