Drill bit, in particular wood drill bit

Abstract

The invention relates to a drill bit (100), in particular a wood drill bit, having a longitudinal central axis (102) and a clamping section (110) for rotationally fixed connection to a tool receptacle, the clamping section (110) being connected to a cutting section (140) by means of a shank section (130), the cutting section forming a head section (150) at an end facing away from the clamping section (110), a centering section (160) is arranged on the head section (150), the head section (150) has a cutting edge (157) with at least two sections (158, 159) which are connected to each other, a first section (158) is arranged at a predetermined angle (199) relative to a second section (159), the first section (158) has a first diameter (105), and the second section (159) has a second diameter (106), the second diameter (106) is smaller than the first diameter (105), and wherein the first section (158) is arranged facing the clamping section (110) and the second section (159) is arranged facing the centering section (160).

Description

Technical Field

[0001] The invention relates to a drill bit, in particular a wood drill bit, having a longitudinal center axis and a clamping section for being connected to a tool receptacle in a rotationally fixed manner, wherein the clamping section is connected to a cutting section via a shank section, the cutting section forming a head section at the end facing away from the clamping section, wherein a centering section is arranged on the head section. Background Art

[0002] Such drill bits in the form of wood drill bits are known from the prior art. The drill bits have a longitudinal center axis and a clamping section which is connected to the tool receptacle in a rotationally fixed manner. The clamping section is connected via a shank section to a cutting section which forms a head section at the end facing away from the clamping section. The centering section is arranged on the head section. Due to the new framework conditions in new power tools, greater forces act on the drill bit due to higher torques, which can lead to relatively rapid wear. Summary of the invention

[0003] The invention relates to a drill bit, in particular a wood drill bit, having a longitudinal center axis and a clamping section for rotationally fixed connection to a tool receptacle, wherein the clamping section is connected to a cutting section via a shank section, the cutting section forming a head section at an end facing away from the clamping section, wherein a centering section is arranged on the head section. The head section has a cutting edge, which has at least two sections connected to one another, wherein a first section is arranged at a predetermined angle to a second section, wherein the first section has a first diameter and the second section has a second diameter, wherein the second diameter is smaller than the first diameter, and wherein the first section is arranged facing the clamping section and the second section is arranged facing the centering section.

[0004] Therefore, the present invention can provide a drill bit having at least two sections of a cutting edge connected to each other at a predetermined angle, thereby reducing the forces acting on the drill bit. Therefore, the wear caused by the forces usually acting on the drill bit can be at least reduced.

[0005] Preferably, the cutting section comprises a first material and the head section comprises a second material, wherein the two materials are different.

[0006] Thus, the material hardness can be increased in a simple and uncomplicated manner and thus an increased wear resistance can be achieved.

[0007] The second material preferably comprises high-speed cutting steel, high-strength carbon steel and / or cemented carbide.

[0008] Thus, a second material having a greater material hardness and improved wear resistance can be provided in a simple manner.

[0009] The head section is preferably fastened to the cutting section by means of a welded connection.

[0010] Therefore, a safe and reliable arrangement of the head section on the cutting section can be achieved.

[0011] Preferably, a predetermined circumferential distance is formed between the outer circumference of the centering section and the outer circumference of the head section, wherein the ratio of the maximum outer diameter of the head section to the predetermined circumferential distance is less than 3.5.

[0012] Thus, a suitable configuration of the head section can be provided in a simple manner.

[0013] Preferably, the first section has a height which is arranged perpendicular to the longitudinal center axis, wherein the height has a value in the range of 1.5 mm to 4 mm.

[0014] A suitable cutting edge or first section can thus be provided in a simple manner.

[0015] According to one embodiment, the head section has a maximum outer diameter of at least 17 mm.

[0016] Thus, a head section can be provided, by means of which a cutting edge having at least two sections can be formed in a simple and uncomplicated manner.

[0017] Preferably, the cutting edge has a first section, a second section and a third section, wherein the first section is arranged at a predetermined angle relative to the second section and the third section is arranged at a predetermined angle relative to the second section.

[0018] Thus, an alternative configuration may be provided in which at least the wear caused by the forces normally acting on the drill bit may be reduced.

[0019] According to one embodiment, the cutting edge has a first step arranged between the first section and the second section and a second step arranged between the first section and the third section, wherein the first step has a first length oriented along the longitudinal center axis and the second step has a second length oriented along the longitudinal center axis, wherein the first length is smaller than the second length.

[0020] Thus, a strictly monotonous cutting edge can be provided in a simple manner.

[0021] Preferably, the maximum outer diameter of the head section is greater than the outer diameter of the shank section.

[0022] Thus, a head section suitable for a drill bit can be provided in a simple manner. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In the following description, the invention is explained in more detail based on the exemplary embodiments shown in the accompanying drawings. The accompanying drawings show:

[0024] Figure 1 : A side view of a drill bit with a cutting edge according to the invention,

[0025] Figure 2 : Figure 1 Front view of the drill bit,

[0026] Figure 3 : Figure 1 and Figure 2 A top view of a magnified area of ​​the drill bit,

[0027] Figure 4 : Figures 1 to 3 A three-dimensional view of a magnified area of ​​the drill bit,

[0028] Figure 5 : Figure 4 The drill bit is relative to Figure 4 Stereoscopic view of the magnified area in a rotating view,

[0029] Figure 6 : Figure 1 A front view of a drill bit with an alternative head section,

[0030] Figure 7 : Figure 6 A top view of a magnified area of ​​the drill bit,

[0031] Figure 8 : Figure 6 and Figure 7 A three-dimensional view of a magnified area of ​​the drill bit,

[0032] Fig. 9 : Figures 6 to 8 The drill bit is relative to Figure 8 Stereoscopic view of the magnified area in a rotating view,

[0033] Fig.10 : Figures 1 to 5 A local longitudinal section of the drill bit,

[0034] Fig.11 : Figures 1 to 5 A side view of the head section of the drill bit,

[0035] Fig.12 : Figures 1 to 11 A longitudinal section of the head section of the drill bit with the hardness measurement points, and

[0036] Fig.13 : With hardness measuring points assigned to Figures 1 to 5 A longitudinal section of the cutting edge of the head section of the drill bit.

[0037] In the figures, elements having the same or similar functions are provided with the same reference symbols and are described in detail only once. DETAILED DESCRIPTION

[0038] Figure 1 An exemplary drill bit 100 is shown, which has a longitudinal center axis 102 and a clamping section 110 for connecting the drill bit 100 to a tool receptacle of a handheld power tool in a rotationally fixed manner. The drill bit 100 is preferably designed as a wood drill bit. The drill bit 100 preferably has an overall length 101 .

[0039] The clamping section 110 is connected to the cutting section 140 via the shank section 130. The shank section 130 preferably comprises a circular cross section with a diameter 103.

[0040] The clamping section 110 is Figure 1 In the example, there are six tangential flattened portions 112. It should be noted that the clamping section 110 can also have more or less than six flattened portions 112. In addition, the clamping section 110 can also be configured as a round shank.

[0041] The cutting section 140 forms a head section 150 at the end facing away from the clamping section 110. The cutting section 140 preferably has a first material and the head section 150 has a second material, wherein the two materials are preferably different. The second material preferably comprises high-speed cutting steel, high-strength carbon steel and / or cemented carbide. The centering section 160 is preferably arranged on the head section 150.

[0042] The head section 150 has a cutting edge 157, which has at least two sections 158, 159 connected to each other. For this purpose, the cutting edge 157 preferably has a strictly monotonous contour. For this purpose, the first section 158 is preferably arranged at a predetermined angle 199 with the second section 159. The predetermined angle 199 is preferably between 25 degrees and 45 degrees, preferably 30 degrees. Preferably, the first section 158 has a first diameter 105 and the second section 159 has a second diameter 106. Here, the second diameter 106 is preferably smaller than the first diameter 105. The first section 158 is preferably arranged facing the clamping section 110, and the second section 159 is arranged facing the centering section 160.

[0043] According to one embodiment, the head segment 150 is fixed to the cutting segment 140 by a welded connection 154. Preferably, the head segment 150 has a maximum outer diameter, which corresponds to the first diameter 105 in the diagram and preferably has at least 17 mm. Preferably, the maximum outer diameter 105 of the head segment 150 corresponds to a diameter of 11 / 16 inches. In this case, the maximum outer diameter 105 of the head segment 150 is preferably greater than the outer diameter 103 of the shank segment 130.

[0044] Preferably, the shank section 130 widens into the cutting section 140 by a flattened portion 132. The diameter 104 of the cutting section 140 is greater than the diameter 103 of the shank section 130. The flattened portion 132 is preferably arranged at an angle 109 to the longitudinal center axis 102. For example, the angle 109 is 25 degrees.

[0045] Preferably, the cutting section 140 has at least two mutually opposite cutting edges 142 , 144 . A cutting edge 157 is preferably assigned to the cutting edges 142 , 144 , ie each cutting edge 142 , 144 has a cutting edge 157 .

[0046] Figure 2 Shown from the front Figure 1 Drill bit 100. Figure 2 Preferably two mutually opposite cutting edges 142 , 144 are shown here schematically, each having a cutting edge 157 .

[0047] Figure 3 Show Figure 1 and Figure 2 The drill head 100 of FIG. 1 and the head section 150 are shown schematically. For example, the first section 158 of the cutting edge 157 has a height 330. The height 330 is arranged schematically parallel to the longitudinal center axis 102 and perpendicular to the longitudinal center axis 102 and preferably has a value in the range of 1.5 mm to 4 mm.

[0048] Figure 4 and Figure 5 Show Figures 1 to 3 A drill head 100 is arranged to rotate about a longitudinal axis 102 . Figure 4 and Figure 5 A head section 150 is shown having two mutually opposite cutting edges 142 , 144 which each have a cutting edge 157 or a first section 158 and a second section 159 .

[0049] Figure 6 Show Figures 1 to 5 An alternative embodiment 400 of a head section 150 of the present invention is provided, which has a cutting edge 257, which has three sections 159, 203, 205 as shown. Here, the first section 203 is preferably arranged at a predetermined angle 213 with the second section 159, and the third section 205 is arranged at a predetermined angle 215 with the second section 159. Preferably, the predetermined angles 213, 215 are between 25 degrees and 45 degrees, preferably 30 degrees.

[0050] Figure 7 Show Figure 6100 and intuitively shows the configuration 400 of the head section 150. Here, the cutting edge 257 has a first step 233 and a second step 235. The first step 233 is preferably arranged between the first section 203 and the second section 159, and the second step 235 is arranged between the first section 203 and the third section 205. Here, the first step 233 has a first length 223 oriented along the longitudinal center axis 102, and the second step 235 has a second length 225 oriented along the longitudinal center axis 102. The first length 223 is preferably smaller than the second length 225. The first length 223 is preferably at least about 3 mm within a predetermined tolerance. In addition, the second length 225 is preferably between 4 mm and 5 mm within a predetermined tolerance.

[0051] Figure 8 and Fig. 9 Show Figure 6 and Figure 7 The drill head 100 is arranged to rotate about a longitudinal axis 102. Figure 8 and Fig. 9 The embodiment 400 of the head section 150 is schematically shown with the cutting edges 142 , 144 arranged opposite one another, each of which has a cutting edge 257 or a first, second and third section 203 , 159 , 205 .

[0052] Fig.10 Show Figures 1 to 5 A portion of the head section 150 of the drill bit 100 . Fig.10 The outer circumference 502 of the centering section 160 is shown schematically, wherein the centering section 160 is Fig.10 Only sections are shown in FIG. Fig.10 The outer circumference 504 of the head section 150 is also shown. In addition, the predetermined circumferential distance 505 formed between the outer circumference 502 of the centering section 160 and the outer circumference 504 of the head section 150 is shown. Preferably, the ratio of the maximum outer diameter of the head section 150 to the predetermined circumferential distance 505 is less than 3.5. For this purpose, the head section 150 has a maximum outer diameter of at least 17 mm, as described above in Figure 1 As described in .

[0053] Fig.11 Show Figures 1 to 5150 and intuitively shows the weld 520 of the welded connection 154, which fixes the head section 150 to the cutting section 140. Preferably, along the longitudinal center axis 102, predetermined distances 611, 612, 615 are formed between the two sections 158, 159 of the cutting edge 157 and the weld 520 of the head section 150. The weld 520 has an arcuate shape, wherein a section of the weld 520 is formed in the first section 158 and another section of the weld 520 (in Fig.11 The cutting section 140 (shown on the right in the figure) is formed next to the first section 158.

[0054] Preferably, a minimum distance 611 and a maximum distance 612 are formed between the second section 159 of the cutting edge 157 and the weld seam 520. In addition, a distance 615 is preferably formed between the right end of the first section 158 shown in the figure and the weld seam 520. Preferably, the predetermined distances 611, 612, 615 are Figures 1 to 5 The ratio of the maximum outer diameter of the head section 150 is, for example, in the range of 0.01 to 1.5.

[0055] Fig.12 Figure 2 shows a hardness measurement with exemplary measuring points A to F during a hardness measurement using a microhardness test. Figures 1 to 5 The head section 150 of the embodiment. In this case, the first material is arranged in the region of the measuring points A and D, and the second material is arranged in the region of the remaining measuring points. According to one embodiment, the first material is C60 and the second material is HS6-5-2.

[0056] For example, during the measurement, an average hardness value of 299 (in HV0.5) was obtained at position A, and an average hardness value of 303 was obtained at position D. At measuring points B, C and E along first section 158 of cutting edge 157, the average hardness values ​​were 827 (B), 849 (C) and 857 (E). Measuring point F is arranged in the region of centering section 160, and an average hardness value of 823 was measured there.

[0057] Fig.13 Show Figures 1 to 5 The cutting edge 142 has three exemplary measurement points G, H, I. The cutting edge 142 has a similar Fig.12 The second material HS6-5-2 is measured. An average hardness value of 823 is measured at measuring point G, an average hardness value of 827 is measured at measuring point H, and an average hardness value of 824 is measured at measuring point I. The above average hardness values ​​are only exemplary and are not intended to limit the present invention.

Claims

1. A drill bit (100), in particular a wood drill bit, having a longitudinal center axis (102) and a clamping section (110) for rotationally fixed connection to a tool receptacle, wherein: The clamping section (110) is connected to the cutting section (140) via a shank section (130), the cutting section forming a head section (150) at an end facing away from the clamping section (110), wherein a centering section (160) is arranged on the head section (150), characterized in that the head section (150) has a cutting edge (157) having at least two sections (158, 159; 203, 205) connected to each other, wherein the first section (158 ; 203) are arranged at a predetermined angle (199; 213) relative to the second section (159), wherein the first section (158) has a first diameter (105) and the second section (159) has a second diameter (106), wherein the second diameter (106) is smaller than the first diameter (105), and wherein the first section (158) is arranged facing the clamping section (110) and the second section (159) is arranged facing the centering section (160).

2. The drill bit according to claim 1, characterized in that The cutting section (140) comprises a first material and the head section (150) comprises a second material, wherein the two materials are different.

3. The drill bit according to claim 2, characterized in that The second material includes high-speed cutting steel, high-strength carbon steel and / or cemented carbide.

4. A drill bit according to any one of the preceding claims, characterised in that The head section (150) is fixed to the cutting section (140) by means of a welding connection.

5. A drill bit according to any one of the preceding claims, characterised in that A predetermined circumferential distance (505) is formed between an outer circumference (502) of the centering section (160) and an outer circumference (504) of the head section (150), wherein a ratio of a maximum outer diameter (105) of the head section (150) to the predetermined circumferential distance (505) is less than 3.

5.

6. A drill bit according to any one of the preceding claims, characterised in that The first section (158) has a height (330) arranged perpendicular to the longitudinal center axis (102), wherein the height has a value in the range of 1.5 mm to 4 mm.

7. A drill bit according to any one of the preceding claims, characterised in that The head section (150) has a maximum outer diameter (105) of at least 17 mm.

8. A drill bit according to any one of the preceding claims, characterised in that The cutting edge (257) has a first section (203), a second section (159) and a third section (205), wherein the first section (203) is arranged at a predetermined angle (213) relative to the second section (159), and the third section (205) is arranged at a predetermined angle (215) relative to the second section (159).

9. The drill bit according to claim 8, characterized in that The cutting edge (257) has a first step (233) arranged between the first section (203) and the second section (159), and a second step (235) arranged between the first section (203) and the third section (205), wherein the first step (233) has a first length (223) oriented along the longitudinal center axis (102), and the second step (235) has a second length (225) oriented along the longitudinal center axis (102), wherein the first length (223) is smaller than the second length (225).

10. A drill bit according to any one of the preceding claims, characterised in that The maximum outer diameter (105) of the head section (150) is greater than the outer diameter (103) of the shank section (130).

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