Cross drill bit structure

Abstract

According to the technical scheme, the cross-shaped drill bit structure is characterized in that the cross-shaped drill bit structure comprises a drill rod, a cutting head is arranged on the drill rod, and the cutting head comprises four side cutting edges located on the outer side of the drill rod and arranged in a cross-shaped structure and a top cutting edge located in the middle of the cross-shaped structure; the top cutting edge comprises a main cutting face and an auxiliary cutting face which are arranged on the opposite sides, the crossed tip end of the main cutting face and the auxiliary cutting face is eccentrically arranged relative to the drill rod and is provided with a chamfering structure, the side cutting edges are provided with cutting parts and concave parts, and the cutting parts and the concave parts of the adjacent side cutting edges are arranged in a staggered mode. The drill bit has the advantages of being good in drilling efficiency, low in heat productivity and long in service life.

Description

Technical Field

[0001] The utility model relates to the technical field of drill bits, and more particularly to a cross drill bit structure. Background Art

[0002] A drill bit is a tool used for drilling or expanding holes. It is generally made of metal and is used to drill through holes or blind holes in solid materials.

[0003] There are various drill bit structures in the prior art. For example, Chinese patent publication number CN216398154U discloses a drill bit comprising a drill rod and a cutter head. The cutter head is fixed to one end of the drill rod. The cutter head has at least two cutting edges, all of which are evenly spaced along the circumference of the cutter head. Each cutting edge includes a vertical section and an inclined section. The length direction of the vertical section is consistent with the axial direction of the drill rod. The inclined section extends from one end of the vertical section toward the centerline of the cutter head. The inclined sections of all cutting edges converge at the centerline of the cutter head to form a cutting tip. The outer surface of the vertical section has an inclined cutting edge surface 1, and the outer surface of the inclined section has an inclined cutting edge surface 2. However, the above-mentioned prior art has been found to have average drilling efficiency and the drill bit is prone to heating during use. Therefore, it is necessary to improve the drill bit structure to solve the above-mentioned problems. Utility Model Content

[0004] In view of the deficiencies in the prior art, the utility model provides a cross drill bit structure with good drilling efficiency, low heat generation and long service life.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a cross drill bit structure, comprising a drill rod, a cutting head being provided on the drill rod, the cutting head comprising four side cutting edges located on the outside of the drill rod and arranged in a cross structure, and a top cutting edge located in the middle of the cross structure, the top cutting edge comprising a main cutting surface and a secondary cutting surface arranged on opposite sides, the tip where the main cutting surface and the secondary cutting surface intersect is eccentrically arranged relative to the drill rod and has a chamfered structure, the side cutting edge is provided with a cutting portion and a recessed portion, and the cutting portion and recessed portion of adjacent side cutting edges are staggered.

[0006] The utility model is further configured as follows: the edge of the main cutting surface forms a first edge and a second edge, the edge of the secondary cutting surface forms a third edge and a fourth edge, the first edge and the third edge are located on the side, and the second edge and the fourth edge are located on the top surface.

[0007] The present invention is further configured as follows: the sharpening length of the first edge is different from the sharpening length of the third edge, and the sharpening length of the second edge is different from the sharpening length of the fourth edge.

[0008] The utility model is further configured such that the length of the cutting portion is smaller than the length of the recessed portion.

[0009] The utility model is further configured as follows: a chip removal groove with a double helical structure is provided on the peripheral side of the drill rod below the cutting head.

[0010] The utility model is further configured as follows: a clamping portion is provided at one end of the drill rod away from the cutting head, and an annular concave bayonet is provided on the clamping portion.

[0011] The present invention is further configured as follows: the clamping portion is configured as a hexagonal prism structure.

[0012] In summary, the present invention has the following beneficial effects:

[0013] Compared with the prior art, the present invention has an eccentrically arranged tip where the main cutting surface and the secondary cutting surface intersect. In this way, during rotary drilling, the eccentrically arranged tip has a wider cutting trajectory coverage during the rotation process, can remove material more quickly, and thus improves the efficiency of hole expansion; and the eccentric structure allows the cutting force to be dispersed to a larger area rather than concentrated on the central axis. When processing hard and brittle materials such as ceramic tiles, it is less likely to cause cracks and chipping of the tiles.

[0014] At the same time, in the present invention, a cutting portion and a recessed portion are provided on the side cutting edge. Therefore, when the side cutting edge rotates, a part of it is in cutting work and a part is in an idle state. The heat generated by the cutting portion due to cutting can be dissipated from the recessed portion, so that the side cutting edge will not be in a friction cutting state during the working process, which greatly reduces the heat generation; and the cutting portion and the recessed portion of adjacent side cutting edges are staggered. In this way, on a rotating surface, the waste chips generated after cutting by the cutting portion of one side cutting edge can leak out from the recessed portion of the adjacent rear side cutting edge, and then be cut by the cutting portion of the other side cutting edge, and so on, forming an alternating cutting work similar to a sawtooth structure. The leakage of waste chips can not only improve the cutting efficiency, but also reduce unnecessary wear, further reduce the heat generated by the friction of waste chips, and better protect the side cutting edge. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the overall structure of the drill bit.

[0016] Figure 2 It is a schematic diagram of the overall structure of the cutting head.

[0017] Figure 3 It is a schematic diagram of the enlarged structure of the top cutting edge.

[0018] Figure 4 It is a schematic diagram of the double helix structure of the chip groove.

[0019] Figure 5 It is a schematic diagram of the perspective dotted structure of the double helix belt of the chip groove.

[0020] Figure markings: 1. drill rod; 2. cutting head; 3. side cutting edge; 31. cutting portion; 32. recessed portion; 4. top cutting edge; 41. main cutting surface; 42. secondary cutting surface; 5. chamfer structure; 6. chip groove; 61. first spiral; 62. second spiral; 7. clamping portion; 8. bayonet; 9. tip; 1a. first edge; 2a. second edge; 3a. third edge; 4a. fourth edge. DETAILED DESCRIPTION

[0021] The present invention will be described in further detail below with reference to the accompanying drawings.

[0022] This embodiment discloses a cross drill bit structure, such as Figure 1-5 As shown, it includes a drill rod 1, on which a cutting head 2 is provided. The cutting head 2 includes four side cutting edges 3 arranged in a cross structure on the outside of the drill rod and a top cutting edge 4 located in the middle of the cross structure. The side cutting edges 3 are mainly used to cut the side walls of the hole when the drill bit is drilling, while the top cutting edge 4 is used to cut the bottom of the hole when the drill bit is drilling. The two cooperate to achieve the drilling work. Figure 2-3 The top cutting edge 4 includes a main cutting surface 41 and a secondary cutting surface 42 arranged on opposite sides. The tip 9 where the main cutting surface 41 and the secondary cutting surface 42 intersect is eccentrically arranged relative to the drill rod 1 and has a chamfer structure 5. First, during the rotation process, the eccentrically arranged tip 9 has a wider coverage of its cutting trajectory than the tip located in the center, and can remove material faster, thereby improving the efficiency of hole expansion. Secondly, the eccentric structure allows the cutting force to be dispersed to a larger area rather than concentrated on the central axis. When processing hard and brittle materials such as tiles, it is not easy for the tiles to crack or collapse, which has a certain protective effect on the processed materials and is less difficult to process.

[0023] Further, refer to Figure 2The side cutting edge 3 is provided with a cutting portion 31 and a recessed portion 32 , and the cutting portion 31 and the recessed portion 32 of adjacent side cutting edges 3 are staggered. The advantage of such an arrangement is that, when the side cutting edge rotates, part of it is in cutting operation and part of it is in an idle state. The heat generated by the cutting portion 31 due to cutting can be dissipated through the recessed portion 32. Compared with the traditional side cutting edge without the recessed portion 32, the side cutting edge 3 of this embodiment will not be in a friction cutting state during operation, which greatly reduces the heat generation. At the same time, the cutting portion 31 and the recessed portion 32 of adjacent side cutting edges 3 are staggered. Therefore, on a rotating horizontal plane, the waste chips generated after cutting by the cutting portion 31 of one side cutting edge can leak out from the recessed portion 32 of the adjacent subsequent side cutting edge, and then be cut by the cutting portion 31 of the other side cutting edge, and the waste chips can leak out from the recessed portion 32 of the next side cutting edge. This is repeated to form an alternating cutting operation similar to a sawtooth structure. The leakage of waste chips can not only improve cutting efficiency, but also reduce unnecessary wear and further reduce the heat generated by the friction of waste chips. Therefore, through the arrangement of the above structure, the heat generation of the entire drill bit is reduced, the drill bit is better protected, and the service life of the drill bit is extended. In addition, due to the high heat generated by existing drill bits, water needs to be added for cooling during operation. In many cases, there are no conditions for continuous water addition during processing, which requires manual drilling and stopping to keep the drill bit from overheating. The structure of this drill bit has low heat generation, so it can maintain a relatively long working time even without water cooling, which greatly facilitates the drilling process of the staff and improves the convenience and efficiency of the drilling process.

[0024] Further, refer to Figure 3 The edge of the main cutting surface 41 forms the first blade 1a and the second blade 2a, and the edge of the secondary cutting surface 42 forms the third blade 3a and the fourth blade 4a. The first blade 1a and the third blade 3a are located on the side, and the second blade 2a and the fourth blade 4a are located on the top. Among them, the second blade 2a and the fourth blade 4a are mainly used to break the material to form a positioning depression, while the first blade 1a and the third blade 3a cut the side surface to preliminarily form a hole and assist the subsequent side cutting edge 3 to expand the hole. In addition, the cutting length of the first blade 1a is different from the cutting length of the third blade 3a, and the cutting length of the second blade 2a is different from the cutting length of the fourth blade 4a. The effect is that blades of different lengths have different cutting trajectories and structural strengths during rotation. The short blade has high strength but a small trajectory and a small cutting amount, while the long blade has a large trajectory, a large cutting amount but low strength. Therefore, by cooperating with two blades of different lengths, a relatively fast cutting speed can be achieved while maintaining the service life.

[0025] Furthermore, preferably, the length of the cutting portion 31 is smaller than the length of the recessed portion 32. This allows for better heat dissipation during the rotary cutting process. Specifically, during the rotation process, the amount of waste chips generated by adjacent cutting portions 31 is also smaller than the space in the recessed portion 32, leaving some margin so that the waste chips can be better discharged from the recessed portion 32, further reducing the heat generated by the friction of the waste chips.

[0026] Further, refer to Figure 4-5 The drill rod 1 is provided with a double helical chip removal groove 6 on the circumference below the cutting head 2. Figure 4 The first spiral 61 and the second spiral 62 are not drawn with perspective dotted lines to ensure clarity. Figure 5 The first and second spirals 61, 62 are shown as dotted lines, indicating that the chip flute 6 is a double-helix structure. This has the advantage that both the first and second spirals 61, 62, individually have a longer pitch. A longer pitch allows internal waste chips to travel a greater distance per unit rotation angle, allowing for faster chip removal. The staggered double helix formation provides the chip flute 6 with more space for accommodating waste chips, similar to that of a shorter-pitch spiral. Therefore, the chip flute 6 of this embodiment has excellent chip removal efficiency. The rapid removal of waste chips reduces wear and heat, protecting the drill bit.

[0027] Furthermore, the drill rod 1 of this embodiment is provided with a clamping portion 7 at one end away from the cutting head 2, and the clamping portion 7 is provided with an annular concave bayonet 8. Preferably, the clamping portion 7 is configured as a hexagonal prism structure. The hexagonal prism clamping portion 7 can well cooperate with and clamp an existing electric drill bit, effectively driving the drill bit to rotate. The bayonet 8 cooperates with a limiting component in the electric drill bit to prevent the drill bit from falling out. Therefore, the drill bit of this embodiment has good adaptability and versatility, and is easy to use.

[0028] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the design concept of the present invention should be included in the scope of protection of the present invention.

Claims

1. A cross drill bit structure, comprising a drill rod (1), characterized in that: The drill rod (1) is provided with a cutting head (2), the cutting head (2) comprising four side cutting edges (3) located outside the drill rod and arranged in a cross structure, and a top cutting edge (4) located in the middle of the cross structure, the top cutting edge (4) comprising a main cutting surface (41) and a secondary cutting surface (42) arranged on opposite sides, the intersecting tip of the main cutting surface (41) and the secondary cutting surface (42) being eccentrically arranged relative to the drill rod (1) and having a chamfer structure (5), the side cutting edge (3) being provided with a cutting portion (31) and a recessed portion (32), and the cutting portions (31) and recessed portions (32) of adjacent side cutting edges (3) being staggered.

2. A cross drill bit structure according to claim 1, characterized in that: The edge of the main cutting surface (41) forms a first edge (1a) and a second edge (2a), and the edge of the secondary cutting surface (42) forms a third edge (3a) and a fourth edge (4a). The first edge (1a) and the third edge (3a) are located on the side, and the second edge (2a) and the fourth edge (4a) are located on the top surface.

3. A cross drill bit structure according to claim 2, characterized in that: The cutting length of the first edge (1a) is different from the cutting length of the third edge (3a), and the cutting length of the second edge (2a) is different from the cutting length of the fourth edge (4a).

4. The cross drill bit structure according to claim 1, characterized in that: The length of the cutting portion (31) is smaller than the length of the recessed portion (32).

5. The cross drill bit structure according to claim 1, characterized in that: The drill rod (1) is provided with a chip removal groove (6) with a double helical structure on the peripheral side below the cutting head (2).

6. The cross drill bit structure according to claim 1, characterized in that: A clamping portion (7) is provided at one end of the drill rod (1) away from the cutting head (2), and an annular concave bayonet (8) is provided on the clamping portion (7).

7. The cross drill bit structure according to claim 6, characterized in that: The clamping portion (7) is configured as a hexagonal column structure.

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