A drill bit for soft materials

Abstract

The present invention provides a drill bit for soft materials, comprising a drill bit body, wherein a first chip groove and a second chip groove are spirally provided on the circumference of the drill bit body, a tip portion is provided at one end of the drill bit body, the tip portion comprising a first cutting face and a second cutting face, the first cutting face and the second cutting face intersecting to form a chisel edge, a first main cutting edge formed between the first cutting face and the first chip groove, a second main cutting edge formed between the second cutting face and the second chip groove, a first clearance portion provided between the first chip groove and the second cutting face, a second clearance portion provided between the second chip groove and the first cutting face, the first clearance portion intersecting with the first cutting face to form a first secondary cutting edge located between the first main cutting edge and the chisel edge, the second clearance portion intersecting with the second cutting face to form a second secondary cutting edge located between the second main cutting edge and the chisel edge. The drill bit for soft materials of the present invention has good chip removal capability, can prevent tool sticking, and can also reduce the drill bit's drilling resistance, thereby significantly reducing the problem of poor chip removal when drilling holes in soft materials.

Description

Technical Field

[0001] The invention relates to the technical field of drilling processing, in particular to a drill bit for soft materials. Background Art

[0002] A twist drill is a common drilling tool for PCB boards. It generally consists of a shank and a cutting part. The drill tip of the cutting part mainly plays a cutting role when drilling. Figure 1 The drill bit of the prior art includes a first main cutting face 100, a second main cutting face 110, a first secondary cutting face 120 and a second secondary cutting face 130. A transverse cutting face grinding groove 160 is provided between the chisel edge 140 and the chip groove 150 of the drill bit to reduce the drilling cutting force of the drill bit. However, for soft materials, when using the drill bit of the prior art for hole processing, deformation, tool sticking and burrs are prone to occur due to the low melting point and insufficient hardness of the soft materials. In particular, the traditional drill bit has too little chip removal space, resulting in the highest cutting temperature being located at the cutting edge. The higher the temperature, the stronger the viscosity of the soft material. When the chip removal space is insufficient, it is easy to generate extrusion pressure, causing the chips to stick to the chip groove, resulting in insufficient chip removal, and even tool breakage.

[0003] Therefore, it is necessary to improve the existing drill bit to meet the hole processing requirements of soft materials. Summary of the Invention

[0004] The purpose of the present invention is to provide a drill bit for soft materials, which has good chip removal ability, prevents the occurrence of tool sticking, and can also reduce the drilling resistance of the drill bit, thereby significantly reducing the problem of poor chip removal when the drill bit is used for soft material hole processing.

[0005] To achieve the above-mentioned objectives, the present invention provides a drill bit for soft materials, comprising a drill bit body, wherein a first chip groove and a second chip groove are spirally provided on the circumferential surface of the drill bit body and are centrally symmetrical along the axial direction of the drill bit body, and a tip is provided at one end of the drill bit body, and the tip comprises a first cutting surface and a second cutting surface that are centrally symmetrical, the first cutting surface and the second cutting surface intersect to form a transverse edge, a first main cutting edge is formed between the first cutting surface and the first chip groove, and a second main cutting edge is formed between the second cutting surface and the second chip groove, a first avoidance portion is provided between the first chip groove and the second cutting surface, a second avoidance portion is provided between the second chip groove and the first cutting surface, the first avoidance portion intersects with the first cutting surface to form a first secondary cutting edge and is located between the first main cutting edge and the transverse edge, and the second avoidance portion intersects with the second cutting surface to form a second secondary cutting edge and is located between the second main cutting edge and the transverse edge.

[0006] Compared with the prior art, the drill bit for soft materials of the present invention has a first chip groove and a second chip groove for chip removal of the first main cutting edge and the second main cutting edge, and a first avoidance portion is provided between the first chip groove and the second blade surface, and a second avoidance portion is provided between the second chip groove and the first blade surface. That is to say, the chisel edge grinding groove and the connected blade surface in the traditional drill bit are ground to form an avoidance portion with a groove structure, and the avoidance space is greatly improved, which can greatly improve the chip removal ability of the drill bit and prevent the occurrence of tool sticking. It can also reduce the chisel edge distance, thereby improving the sharpness of the drill bit to reduce the drilling resistance of the drill bit, and can greatly reduce the problem of poor chip removal when the drill bit is used for soft material hole processing.

[0007] Preferably, the circumferential surface of the drill body is spirally provided with a first edge band and a second edge band that are centrally symmetrical along the axial direction of the drill body, a first avoidance groove is provided between the second edge band and the first chip groove, and a second avoidance groove is provided between the first edge band and the second chip groove.

[0008] Preferably, the first cutting surface includes a first main cutting surface and a first chamfered surface, the first main cutting edge includes a first main cutting edge and a first chamfered cutting edge, the first chamfered surface is located between the first edge band and the first main cutting surface, the first main cutting edge is formed between the first main cutting surface and the first chip groove, and the first chamfered cutting edge is formed between the first chamfered surface and the first chip groove.

[0009] The second cutting surface includes a second main cutting surface and a second chamfered surface, the second main cutting edge includes a second main cutting edge and a second chamfered cutting edge, the second chamfered surface is located between the second edge band and the second main cutting surface, the second main cutting edge is formed between the second main cutting surface and the second chip groove, and the second chamfered cutting edge is formed between the second chamfered surface and the second chip groove.

[0010] The helix angles of the first chip removal groove and the second chip removal groove are both 20 degrees to 50 degrees.

[0011] Preferably, the first space-avoiding portion is a cylindrical surface.

[0012] Preferably, the axial angle of the first clearance portion is smaller than the helix angle of the first chip removal groove.

[0013] Preferably, the axial angle of the first clearance portion differs from the helical angle of the first chip removal groove by 0 degrees to 10 degrees.

[0014] Preferably, the chamfer of the first chamfered surface and the chamfer of the second chamfered surface are both 80 degrees to 100 degrees. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0016] Figure 1 It is a structural diagram of a drill bit in the prior art.

[0017] Figure 2 It is a three-dimensional diagram of the drill bit for soft materials of the present invention.

[0018] Figure 3 yes Figure 2 A three-dimensional view of a drill bit for soft materials from another angle.

[0019] Figure 4 yes Figure 2 Top view of a drill bit for soft materials shown.

[0020] Figure 5 and Figure 2 The same is used to illustrate the axial angle α of the first gap-avoiding portion.

[0021] Description of reference numerals:

[0022] Drill body 10, first chip groove 11, second chip groove 12, tip 13, first cutting surface 14, first main cutting surface 141, first chamfered surface 143, second cutting surface 15, second main cutting surface 151, second chamfered surface 153, chisel edge 16, first main cutting edge 17, first cutting main edge 171, first chamfered cutting edge 173, second main cutting edge 18, second cutting main edge 181, second chamfered cutting edge 183, first avoidance portion 19, second avoidance portion 20, first secondary cutting edge 21, second secondary cutting edge 22, first edge band 23, second edge band 24, first avoidance groove 25, second avoidance groove 26, cylindrical rotation axis 27, center axis 28. DETAILED DESCRIPTION

[0023] In order to explain the technical content and structural features of the present invention in detail, the following is a further description in conjunction with the embodiments and the accompanying drawings.

[0024] See also Figure 2-Figure 4The present invention provides a drill bit for soft materials, including a drill bit body 10, wherein a first chip removal groove 11 and a second chip removal groove 12 are spirally provided on the circumference of the drill bit body 10 and are centrally symmetrical along the axial direction of the drill bit body 10, a tip 13 is provided at one end of the drill bit body 10, and the tip 13 includes a first cutting surface 14 and a second cutting surface 15 which are centrally symmetrical, wherein the first cutting surface 14 and the second cutting surface 15 intersect to form a chisel edge 16, and a first main cutting edge 17 is formed between the first cutting surface 14 and the first chip removal groove 11, and the second main cutting edge 17 is formed between the first cutting surface 14 and the first chip removal groove 11. A second main cutting edge 18 is formed between the cutting surface 15 and the second chip groove 12, a first avoidance portion 19 is provided between the first chip groove 11 and the second cutting surface 15, a second avoidance portion 20 is provided between the second chip groove 12 and the first cutting surface 14, the first avoidance portion 19 intersects with the first cutting surface 14 to form a first secondary cutting edge 21 and is located between the first main cutting edge 17 and the chisel edge 16, the second avoidance portion 20 intersects with the second cutting surface 15 to form a second secondary cutting edge 22 and is located between the second main cutting edge 18 and the chisel edge 16.

[0025] It can be understood that in the drill bit for soft materials of the present invention, the first chip groove 11 and the second chip groove 12 are used for chip removal of the first main cutting edge 17 and the second main cutting edge 18 and the first secondary cutting edge 21 and the second secondary cutting edge 22, and a first avoidance portion 19 is provided between the first chip groove 11 and the second cutting surface 15, and a second avoidance portion 20 is provided between the second chip groove 12 and the first cutting surface 14. That is to say, the chisel edge grinding groove and the corresponding cutting surface connected to the traditional drill bit are ground to form an avoidance portion with a groove structure, and the avoidance space is greatly improved, which can greatly improve the chip removal ability of the drill bit and prevent the occurrence of tool sticking. It can also reduce the distance of the chisel edge 16, thereby improving the sharpness of the drill bit to reduce the drilling resistance of the drill bit, and can greatly reduce the problem of poor chip removal when the drill bit is used for soft material hole processing.

[0026] Please refer to Figure 2-Figure 3 The drill body 10 is spirally provided with a first edge band 23 and a second edge band 24 which are centrally symmetrical along the axial direction of the drill body 10. A first avoidance groove 25 is provided between the second edge band 24 and the first chip groove 11, and a second avoidance groove 26 is provided between the first edge band 23 and the second chip groove 12. During the drilling process, the first edge band 23 and the second edge band 24 have a guiding function, which can ensure the stability of the drilling process, and the first edge band 23 and the second edge band 24 can play a supporting role during the drilling process, thereby ensuring the hole position accuracy of the hole processing. At the same time, by providing the first avoidance groove 25 and the second avoidance groove 26, the avoidance space is increased, the heat dissipation is accelerated, and the temperature is effectively reduced, which is further beneficial to reducing the temperature of the first main cutting edge 17 and the second main cutting edge 18, and reducing the risk of tool breakage.

[0027] Please refer to Figure 4The first cutting surface 14 includes a first main cutting surface 141 and a first chamfered surface 143, the first main cutting edge 17 includes a first main cutting edge 171 and a first chamfered cutting edge 173, the first chamfered surface 143 is located between the first blade band 23 and the first main cutting surface 141, the first main cutting edge 171 is formed between the first main cutting surface 141 and the first chip groove 11, and the first chamfered cutting edge 173 is formed between the first chamfered surface 143 and the first chip groove 11, the second cutting surface 15 includes a second main cutting surface 151 and a second chamfered surface 153, the second main cutting edge 18 includes a second main cutting edge 181 and a second chamfered cutting edge 183, the second chamfered surface 153 is located between the second blade band 24 and the second main cutting surface 151, the second main cutting edge 181 is formed between the second main cutting surface 151 and the second chip groove 12, and the second chamfered cutting edge 183 is formed between the second chamfered surface 153 and the second chip groove 12. It can be understood that by setting the first chamfered surface 143 and the second chamfered surface 153, during the drilling process, the first chamfered cutting edge 173 and the second chamfered cutting edge 183 can reduce the size of burrs at the drill hole exit, thereby avoiding the generation of burrs and improving the drilling quality.

[0028] In some embodiments, the helix angles of the first and second chip flutes 11, 12 are both 20-50 degrees. Setting the helix angles of the first and second chip flutes 11, 12 to 20-50 degrees provides a drill bit for soft materials with good rigidity and strength and excellent chip removal. For example, the helix angles of the first and second chip flutes 11, 12 are both 20, 25, 30, 35, 40, 45, and 50 degrees, but are not limited to these values. Other values ​​within the aforementioned ranges are also applicable.

[0029] Please refer to Figure 4-Figure 5, the axial angle α of the first avoidance portion 19 is smaller than the helix angle of the first chip groove 11. This design can improve the smoothness of chip removal. It can be understood that the first avoidance portion 19 is a concave curved surface formed between the first chip groove 11 and the first cutting surface 14 and the second cutting surface 15. In this embodiment, the first avoidance portion 19 is a curved surface formed between the first chip groove 11 and the first main cutting surface 141, the second main cutting surface 151 and the second chamfered surface 153. Similarly, the axial angle of the second avoidance portion 20 is smaller than the helix angle of the second chip groove 12. The second avoidance portion 20 is a curved surface formed between the second chip groove 12 and the second main cutting surface 151, the first main cutting surface 141 and the first chamfered surface 143. In a preferred embodiment, the first escape portion 19 is a cylindrical surface. It can also be understood that the surface formed by the intersection of the first escape portion 19 and the tip 13 is a cylindrical surface. The angle between the cylindrical rotation axis 27 of the first escape portion 19 and the central axis 28 of the drill body 10 is defined as the axial angle of the first escape portion 19 (the second escape portion 20 can refer to the description of the first escape portion 19). In some embodiments, the axial angle α of the first escape portion 19 differs from the helix angle of the first chip flute 11 by 0 degrees to 10 degrees, which is more conducive to improving chip removal capacity and reducing drilling resistance. As an example, the axial angle α of the first escape portion 19 differs from the helix angle of the first chip flute 11 by 0 degrees, 1 degree to 5 degrees, 1 degree to 8 degrees, 2 degrees to 9 degrees, or 5 degrees to 10 degrees, etc., but is not limited to the listed values. Other values ​​not listed within the above numerical ranges are also applicable. In a specific embodiment, for example, the helix angles of the first chip groove 11 and the second chip groove 12 are both 40 degrees, and the axial angles of the first gap 19 and the second gap 20 are both 35 degrees. For another example, the helix angles of the first chip groove 11 and the second chip groove 12 are both 45 degrees, and the axial angles of the first gap 19 and the second gap 20 are both 38 degrees, but the present invention is not limited thereto.

[0030] Please refer to Figure 4-Figure 5 The chamfers of the first chamfered surface 143 and the second chamfered surface 153 are both 80-100 degrees, which can effectively improve the deburring effect. It should be noted that the chamfer of the first chamfered surface 143 refers to the angle between the first chamfered surface 143 and the first main cutting surface 141; the chamfer of the second chamfered surface 153 refers to the angle between the second chamfered surface 153 and the second main cutting surface 151. By way of example, the chamfers of the first chamfered surface 143 are 80 degrees, 82 degrees, 84 degrees, 86 degrees, 88 degrees, 90 degrees, 92 degrees, 94 degrees, 96 degrees, 98 degrees, and 100 degrees; and the chamfers of the second chamfered surface 153 are 80 degrees, 82 degrees, 84 degrees, 86 degrees, 88 degrees, 90 degrees, 92 degrees, 94 degrees, 96 degrees, 98 degrees, and 100 degrees, but are not limited to the listed values. Other values ​​not listed within the above numerical ranges are also applicable.

[0031] The above disclosure is only a preferred embodiment of the present invention and cannot be used to limit the scope of the present invention. Therefore, equivalent changes made according to the claims of the present invention are within the scope of the present invention.

Claims

1. A drill bit for soft materials, comprising a drill bit body, wherein a first chip removal groove and a second chip removal groove are spirally provided on the circumference of the drill bit body and are centrally symmetrical along the axial direction of the drill bit body, characterized in that: One end of the drill body is provided with a tip, and the tip includes a first cutting surface and a second cutting surface that are centrally symmetrical, the first cutting surface and the second cutting surface intersecting to form a chisel edge, a first main cutting edge formed between the first cutting surface and the first chip groove, a second main cutting edge formed between the second cutting surface and the second chip groove, a first avoidance portion is provided between the first chip groove and the second cutting surface, a second avoidance portion is provided between the second chip groove and the first cutting surface, the first avoidance portion intersects with the first cutting surface to form a first secondary cutting edge and is located between the first main cutting edge and the chisel edge, the second avoidance portion intersects with the second cutting surface to form a second secondary cutting edge and is located between the second main cutting edge and the chisel edge, the axial angle of the first avoidance portion and the axial angle of the second avoidance portion are both smaller than the helix angle of the first chip groove, and the first avoidance portion and the second avoidance portion are both concave curved surfaces.

2. The drill bit for soft materials according to claim 1, characterized in that: The drill body is spirally provided with a first edge band and a second edge band that are centrally symmetrical along the axial direction of the drill body, a first avoidance groove is provided between the second edge band and the first chip groove, and a second avoidance groove is provided between the first edge band and the second chip groove.

3. The drill bit for soft materials according to claim 2, characterized in that: The first cutting surface includes a first main cutting surface and a first chamfered surface, the first main cutting edge includes a first main cutting edge and a first chamfered cutting edge, the first chamfered surface is located between the first edge band and the first main cutting surface, the first main cutting edge is formed between the first main cutting surface and the first chip groove, and the first chamfered cutting edge is formed between the first chamfered surface and the first chip groove. The second cutting surface includes a second main cutting surface and a second chamfered surface, the second main cutting edge includes a second main cutting edge and a second chamfered cutting edge, the second chamfered surface is located between the second edge band and the second main cutting surface, the second main cutting edge is formed between the second main cutting surface and the second chip groove, and the second chamfered cutting edge is formed between the second chamfered surface and the second chip groove.

4. The drill bit for soft materials according to claim 1, characterized in that: The helix angles of the first chip removal groove and the second chip removal groove are both 20 degrees to 50 degrees.

5. The drill bit for soft materials according to claim 1, characterized in that: A surface formed by the intersection of the first space-avoiding portion and the tip portion is a cylindrical surface.

6. The drill bit for soft materials according to claim 1, characterized in that: The axial angle of the first clearance portion differs from the helix angle of the first chip removal groove by 0 degrees to 10 degrees.

7. The drill bit for soft materials according to claim 3, characterized in that: The chamfer angles of the first chamfered surface and the second chamfered surface are both 80 degrees to 100 degrees.

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