MACHINING TOOL HAVING ASYMMETRICAL TEETH HAVING CUTTING PARTICLES

Abstract

A machining tool (1) includes a tooth (3) having a tooth tip (4) being covered with cutting particles (5) to form a plurality of geometrically undefined cutting portions. The tooth tip (4) is designed to be asymmetrical. The machining tool (1) thus is a 2-in-1 machining tool including differently designed sides of the tooth tips (4) which are suitable for efficiently machining different materials.

Claims

1. A machining tool, comprising: a tooth having a tooth tip being covered with cutting particles to form a plurality of geometrically undefined cutting portions, the tooth tip being designed to be asymmetrical, the tooth tip including a longitudinal center axis, a plateau surface, a first connecting surface and a second connecting surface, the first connecting surface and the second connecting surface being directly or indirectly connected to the plateau surface, the first connecting surface extending at a first side of the longitudinal center axis under a first tooth tip angle having a first value with respect to the plateau surface, the second connecting surface extending at an opposite second side of the longitudinal center axis under a second tooth tip angle having a different second value with respect to the plateau surface, the first tooth tip angle being <0° as seen in a first sense of direction of movement in which the first connecting surface precedes the second connecting surface, and the second tooth tip angle being ≥0° in an opposite second sense of direction of movement in which the second connecting surface precedes the first connecting surface.

2. The machining tool of claim 1, wherein the first tooth tip angle is between <0° and −80° and the second tooth tip angle is between 0° and 20°

3. The machining tool of claim 1, wherein the first tooth tip angle is between −40° and −80° and the second tooth tip angle is between 5° and 15°.

4. The machining tool of claim 1, wherein the cutting particles include monocrystalline diamond (MCD), polycrystalline diamond (CVD-D), polycrystalline diamond (PCD), cubic bornitride (CBN), cutting ceramics, carbide or combinations thereof.

5. The machining tool of claim 1, wherein the tooth tip is furthermore covered with buffer particles of a different material than the cutting particles, the buffer particles being located between the cutting particles.

6. The machining tool of claim 5, wherein the cutting particles and the buffer particles are partly embedded in a metal layer.

7. The machining tool of claim 6, wherein the metal layer consists of metal that has deposited on the tooth tip as metal ions during galvanization or chemical metal deposition, the metal ions and the metal of the metal layer not being the buffer particles.

8. The machining tool of claim 5, wherein the covered part of the tooth tip consists of between approximately 10% and 60% buffer particles.

9. The machining tool of claim 5, wherein the cutting particles and the buffer particles have approximately the same average size.

10. The machining tool of claim 9, wherein the average size of the cutting particles and the average size of the buffer particles is between approximately 60 μm and 800 μm.

11. The machining tool of claim 5, wherein the buffer particles have a lower hardness than the cutting particles.

12. The machining tool of claim 5, wherein the buffer particles have a lower heat resistance than the cutting particles.

13. The machining tool of claim 5, wherein the buffer particles include monocrystalline diamond (MCD), polycrystalline diamond (CVD-D), polycrystalline diamond (PCD), cubic bornitride (CBN), silicon carbide, cutting ceramics, carbide, plastic, glass, ceramics, boron carbide, nickel, copper or combinations thereof.

14. The machining tool of claim 5, wherein the cutting particles include cubic bornitride (CBN) and the buffer particles include diamond, or the cutting particles include diamond, silicon carbide, plastic, glass, ceramics, boron carbide, nickel, copper or combinations thereof and the buffer particles include plastic, glass, ceramics, boron carbide, nickel, copper or combinations thereof.

15. The machining tool of claim 1, wherein a multitude of such teeth is arranged at the machining tool.

16. The machining tool of claim 1, further comprising a tooth supporting body being designed to be band-shaped or to have the shape of a circular disk.

17. The machining tool of claim 16, wherein the teeth are arranged at the tooth supporting body with a variable division.

18. A method of machining two workpieces of different materials with exactly one machining tool, the machining tool including a tooth having an asymmetrical tooth tip being covered with cutting particles to form a plurality of geometrically undefined cutting portions, comprising the steps of: inserting the machining tool in a first orientation into a machining apparatus including a motor; machining a first workpiece of a first material with the machining tool in the first orientation by driving the machining tool in a first sense of direction of movement; and a1. Switching the motor to drive the machining tool in an opposite second sense of direction of movement, and a2. Machining a second workpiece of a different second material with the machining tool in the first orientation; or b1. Removing the machining tool from the machining apparatus, b2. Inserting the machining tool in an opposite second orientation in the machining apparatus, and b3. Machining a second workpiece of a different second material with the machining tool in the second orientation by driving the machining tool (1) in the first sense of direction of movement.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0073] In the following, the invention is further explained and described with respect to preferred exemplary embodiments illustrated in the drawings.

[0074] FIG. 1 illustrates a perspective view of a part of a first exemplary embodiment of the new machining tool.

[0075] FIG. 2 illustrates a side view of the machining tool according to FIG. 1.

[0076] FIG. 3 illustrates a view from above of the machining tool according to FIG. 1.

[0077] FIG. 4 illustrates a view from the front of the machining tool according to FIG. 1.

[0078] FIG. 5 illustrates the detail B of the machining tool from FIG. 2.

[0079] FIG. 6 illustrates the machining tool according to FIG. 1 without illustrating the cutting particles.

[0080] FIG. 7 illustrates the machining tool according to FIG. 2 without illustrating the cutting particles.

[0081] FIG. 8 illustrates that detail B according to FIG. 5 without illustrating the cutting particles.

[0082] FIG. 9 illustrates a perspective view of a second exemplary embodiment of the new machining tool without illustrating the cutting particles.

[0083] FIG. 10 illustrates a side view of the machining tool according to FIG. 9.

[0084] FIG. 11 illustrates a perspective view of a third exemplary embodiment of the new machining tool without illustrating the cutting particles.

[0085] FIG. 12 illustrates a side view of the machining tool according to FIG. 11.

[0086] FIG. 13 illustrates a side view of a fourth exemplary embodiment of the new machining tool without illustrating the cutting particles.

[0087] FIG. 14 illustrates a perspective view of a part of the machining tool according to FIG. 13.

[0088] FIG. 15 illustrates the detail B from FIG. 13.

[0089] FIG. 16 illustrates the detail A from FIG. 13.

[0090] FIG. 17 illustrates a tooth tip of a tooth of a fifth exemplary embodiment of the new machining tool from the front.

[0091] FIG. 18 illustrates a detail of a tooth tip according to a fifth exemplary embodiment of the new machining tool.

[0092] FIG. 19 illustrates a detailed view corresponding to FIG. 8 of a tooth tip according to another exemplary embodiment of the new machining tool.

[0093] FIG. 20 illustrates a detailed view corresponding to FIG. 8 of a tooth tip according to another exemplary embodiment of the new machining tool.

[0094] FIG. 21 illustrates a detailed view corresponding to FIG. 8 of a tooth tip according to another exemplary embodiment of the new machining tool.

[0095] FIG. 22 illustrates a detailed view corresponding to FIG. 8 of a tooth tip according to another exemplary embodiment of the new machining tool.

DETAILED DESCRIPTION

[0096] FIGS. 1-5 illustrate different views of a first exemplary embodiment of a new machining tool 1. The machining tool 1 includes a tooth supporting body 2. In the present case, this is an elongated band-shaped machining tool 1 of which only a section is illustrated. It is to be understood that the machining tool 1 thus respectively extends further beyond the abruption lines shown in FIG. 1. However, the machining tool 1 could also have the shape of a circular disk. The following statements also apply to such an embodiment.

[0097] The machining tool 1 includes a plurality of teeth 3 being arranged at the tooth supporting body 2. The teeth 3 may be designed to be partly or fully integral with the tooth supporting body 2. In the present example, the teeth 3 are arranged at the tooth supporting body 2 with a constant division. However, they could also be arranged at the tooth supporting body 2 with a variable division.

[0098] The teeth 3 each include a tooth tip 4 facing away from the tooth supporting body 2. The tooth tip 4 is fully or partly covered by (or equipped with) cutting particles 5 and buffer particles 6 in a cutting particle cover region 15. The cutting particles 5 are hard or highly hard. For example, the material may be corundum (Al.sub.2O.sub.3), monocrystalline diamond (MCD), polycrystalline diamond (CVD-D) and the like. For reasons of clarity, only a few of the cutting particles are designated with the reference numeral 5. The ending of the cutting particle cover region 15 in which the cutting particles 5 are located is symbolized by a horizontal line.

[0099] The shape of the tooth tip 4 can be seen easier in the illustrations of FIGS. 6, 7 and 8. Compared to the respective FIGS. 1, 2 and 5, the cutting particles are not illustrated in these figures. However, it is to be understood that the cutting particles also exist in these figures and the following figures. Once again, the ending of the region in which cutting particles exist is symbolized by a horizontal line.

[0100] The tooth tips 4 each include a longitudinal center axis 6, a plateau surface 7, a first connecting surface 8 and a second connecting surface 9. The first connecting surface 8 and the second connecting surface 9 are located directly next to the plateau surface 7. However, it would also be possible that there was an indirect connection, i.e. another surface was located between the plateau surface 7 and the respective connecting surface 8, 9.

[0101] The tooth tip 4 is designed to be asymmetrical. This means that the first connecting surface 8 extends at a first side of the longitudinal center axis 6 (in this case: the left side) under a first tooth tip angle 10 having a first value with respect to the plateau surface 7 and that the second connecting surface 9 extends at an opposite second side of the longitudinal center axis 6 (in this case: the right side) under a second tooth tip angle 11 having a different second value with respect to the plateau surface 7 (see FIG. 8).

[0102] The tooth tip angles 10, 11 are herein defined with respect to a vertical line. In case of the illustrated exemplary embodiment, the value of the first tooth tip angle 10 is approximately 45° and the value of the second tooth tip angle 11 is approximately 20°.

[0103] When the machining tool 1 is moved in a first sense of direction of movement 13 (in this case: to the left), the first connecting surface 8 is the active machining surface which first gets in contact with the material of the workpiece to be machined. The first tooth tip angle 10 is a negative tooth tip angle as seen in this first sense of direction of movement 13. The machining tool has gentle machining properties when machining in this first sense of direction of 13, and it is especially well suitable to machine brittle materials.

[0104] However, when the machining tool 1 is driven and moved in the opposite second sense of direction of movement 14 (in this case: to the right), the second connecting surface 9 is the active machining surface. For example, this may be realized by inverting the rotation direction of the motor of the machining apparatus driving the machining tool 1. Another possibility to activate the second connecting surface 9 is to invert the orientation (arrangement) of the machining tool 1 in the machining apparatus. In both cases, it is achieved that the active machining surface now has a positive tooth angle which results in more aggressive machining properties. Now, one and the same machining tool 1 is especially well suitable for machining ductile materials.

[0105] FIGS. 9 and 10 illustrate a second exemplary embodiment of the new machining tool 1. This embodiment has a lot in common with the above-described embodiments such that it is referred to the above statements to prevent unnecessary repetitions. The same applies to the additional below-described embodiments.

[0106] In contrast thereto, the teeth 3 are located at the tooth supporting body 2 with a variable division which can be seen from the longer dash-dotted lines in FIG. 10. The distance between the first tooth 3 and the second tooth 3 is greater than the distance between the second tooth 3 and the third tooth 3 (see FIG. 10: as seen from the left towards the right). The distance between the third tooth 3 and the fourth tooth 3 is smaller than the distance between that second tooth 3 and the third tooth 3. However, the variable division could also be different.

[0107] FIGS. 11 and 12 illustrate a third exemplary embodiment of the new machining tool 1. In this case, the teeth 3 have different designs among each other. In addition to the above-described first type of teeth 3 (FIG. 12: the second tooth 3 and the third tooth 3 as seen from the left), there is a second type of teeth 3 (FIG. 12: the first tooth 3 and the fourth tooth 3 as seen from the left) in which both tooth tip angles 10, 11 are negative. The tooth tip 4 is also designed to be asymmetrical in these teeth 3 since the values of the tooth tip angles 10, 11 are different. The value of the first tooth tip angle 10 of the first tooth 3 here is approximately 45°, while the value of the second tooth tip angle 11 of the first tooth 3 is approximately 20°. The value of the first tooth tip angle 10 of the fourth tooth 3 is also approximately 45°, while the value of the second tooth tip angle 11 of the fourth tooth 3 is approximately 10°. The teeth 3 are arranged at the tooth supporting body 2 with a constant division. However, they could also be arranged with a variable division.

[0108] FIGS. 13-16 illustrate different views of a fourth exemplary embodiment of the new machining tool 1. In this case, the machining tool 1 is designed as a circular machining blade, i.e. the tooth supporting body 2 has the shape of a circular disk. The teeth 3 are arranged at the tooth supporting body 2 with a variable division. The first tooth tip angle 10 is negative. Its value is approximately 45°. The second tooth tip angle 11 is approximately 2°.

[0109] FIGS. 17 and 18 illustrate a fifth exemplary embodiment of the new machining tool 1. In this case, the tooth tip 4 is not only covered with cutting particles 5, but instead also with buffer particles 16. The cutting particles 5 and the buffer particles 16 are fixedly located in a metal layer 17, and they are partly embedded in this metal layer 17. Thus, they partly protrude from the metal layer 17. The metal layer 17 especially is a galvanic deposition layer or a chemical metal deposition layer.

[0110] The cutting particles 5 and the buffer particles 16 differ with respect to their materials and their functions to be fulfilled. In this regard, it is referred to the above detailed explanations.

[0111] The cutting particles 5, the buffer particles 16 and the metal layer 17 commonly form a cover region 18 fulfilling the desired machining function of the machining tool 1 by including the cutting portions being required for this purpose. This cover region 18 extends over the entire tooth tip 4 or over a part of the tooth tip 4. This is the covered part of the tooth tip 4.

[0112] It is to be understood that the illustrations of FIGS. 17 and 18 are not true to scale and that the shape of the particles 5, 16 practically is different or may be different. The particles 5, 16 may also have approximately the same shape. The illustration intends to make it possible to differentiate the particles 5, 16 and to emphasize that, due to the arrangement of the buffer particles 16, one attains free spaces between the cutting particles 5. These free spaces would not exist or not to such an extent when only arranging cutting particles 5 as this is known in the prior art.

[0113] With respect to additional possible designs of the machine tool 1 and of the tooth tips 4, it is referred to the statements with respect to FIGS. 1-16. In other words, the embodiments of the machining tool 1 according to FIGS. 1-16 may include the buffer particles 16.

[0114] FIGS. 19-22 illustrate detailed views corresponding to FIG. 8 of additional exemplary embodiments of the tooth tip 4 of the machining tool 1. In these embodiments, the tooth tip for is formed and partly formed, respectively, by a separately produced attachment element 19. The attachment element 19 is fixedly connected to the remaining part of the tooth 3 via a connecting zone 20. Suitable connecting methods are gluing, soldering, brazing or welding, for example. The connecting zone 20 is symbolically illustrated by the thicker black line.

[0115] It is perceptible from the different embodiments that the first connecting surface 8 of the attachment element 19 forming the free tooth tip 4 may substantially correspond to or differ from the directly adjacent region of the first connecting surface 8 of the remaining part of the tooth 3. The same applies to the second connecting surface 9.

[0116] The attachment element 19 may be designed as a sintered element. The sintered element is made of a mixture of a binder and of the cutting particles. For example, the binder may be copper, cobalt, iron, bronze, nickel or mixtures thereof. It is also possible that there are buffer particles in addition.

[0117] Many variations and modifications may be made to the preferred embodiments of the invention without departing substantially from the spirit and principles of the invention. All such modifications and variations are intended to be included herein within the scope of the present invention, as defined by the following claims.