Stepped anchor rod drill bit

Abstract

A stepped anchor rod drill bit comprises a drill handle and a drill bit base which are integrally formed, the drill bit base at least comprises two wing bodies which are spirally arranged with the axis of the drill bit as the center, at least two seat bodies are spirally arranged on the upper portions of the wing bodies with the axis of the drill bit as the center, and the heights of the seat bodies are sequentially reduced in a stepped mode from inside to outside. A circular groove is formed in the inner end face of the base body, columnar blades are installed in the circular groove in a matched mode, and the side faces of the adjacent columnar blades are attached to each other. The inner seat body and the columnar blades on the inner seat body protrude out of the wing bodies in the middle, a drill hole with a small hole diameter can be formed in the center portion firstly during screw-in cutting, then the outer seat body and the columnar blades on the outer seat body are used for screw-in cutting to expand the hole diameter, and the drilling effect of stepped step-by-step rotary cutting can be achieved. The large precession cutting area of an existing single columnar blade and decomposition of cutting stress are achieved, the phenomenon that the columnar blade is prone to being rapidly abraded or falling off is avoided, the service life of the drill bit is effectively prolonged, and the cutting and drilling efficiency of the drill bit is effectively improved.

Description

Technical Field

[0001] The invention relates to the technical field of drill bits for engineering and mining, and in particular to a stepped anchor drill bit. Background Art

[0002] Anchor drill bits are drilling tools used in mines, tunnels and other underground projects. They are mainly used to drill holes and install anchors. Anchors are reinforcement materials used to support rocks or soil, which can improve the safety and stability of underground projects. Anchor drill bits are usually made of high-strength alloy steel, with carbide blades or diamond blades on the surface. They are used to cut rocks or soil. When in use, they are connected to a drill rig, which transmits power to it and provides the required thrust and torque.

[0003] The end face of the wing body of the existing anchor drill bit is usually inlaid with a cylindrical blade whose size basically covers the end face size of the wing body. When the drill bit is screwed into the hole, the cylindrical blade undertakes the cutting task. For details, please refer to the anchor drill bit proposed in the authorization announcement No. CN202645431U. The problem existing in the use of the anchor drill bit is that since the size of the cylindrical blade basically covers the end face size of the wing body, the size of the hole formed by the cutting and screwing in of adjacent cylindrical blades is the final anchor hole diameter size, resulting in a larger area of ​​cutting by the cylindrical blade, greater cutting force, and higher drilling power requirements for the drilling rig. The cylindrical blade is easy to wear quickly, and the cylindrical blade often falls off, affecting the service life and drilling efficiency of the drill bit, which needs to be optimized and improved. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a stepped anchor drill bit.

[0005] The technical solution of the present invention is: a stepped anchor drill bit, including an integrally formed cylindrical drill shank and a drill base, the drill base including at least two wing bodies spirally arranged with the drill bit axis as the center, the outer side surfaces of the wing bodies are located on the same cylindrical surface, the size of the cylindrical surface is larger than the size of the cylindrical surface of the drill shank, at least two seat bodies are spirally arranged on the upper part of the wing bodies with the drill bit axis as the center, the heights of these seat bodies decrease in a stepped manner from the inside to the outside, forming a cutting structure that protrudes from the center to the outside, a circular groove is provided on the inner end surface of the seat body, the inner end portions of the two circular grooves overlap, a columnar blade is matched and installed in the circular groove, the thickness of the columnar blade is the same as the depth of the circular groove, and the side surfaces of adjacent columnar blades are arranged to fit each other to reduce the cutting resistance generated in the gap between the two.

[0006] Preferably, the seat body on the wing body is set to two, namely an inner seat body and an outer seat body. The height of the inner seat body is higher than that of the outer seat body. This double seat body structure can not only meet the requirements of multi-stage cutting, but also is easy to process and manufacture, and has low cost. The inner side surface of the inner seat body and the inner side surface of the wing body are located in the same plane, and the outer side surface of the outer seat body and the outer side surface of the wing body are located on the same cylindrical surface.

[0007] Preferably, the surface of the protruding portion of the seat body is an arc-shaped surface, which is coplanar with the cylindrical surface of the columnar blade. During cutting, the columnar blade can cover the seat body to reduce its wear.

[0008] Preferably, an arc-shaped transition groove is provided between the arc-shaped surfaces of adjacent seat bodies, and the adjacent seat bodies are smoothly transitionally connected as a whole through the arc-shaped transition groove, thereby reducing cutting resistance and playing a role in slag removal.

[0009] Preferably, the diameter of the columnar blade is 5-10 mm and the thickness is 2-5 mm. This size design decomposes the existing single columnar blade into a smaller one, thereby reducing the cutting resistance.

[0010] Preferably, a gap is provided between adjacent wing bodies, and a water injection hole penetrating to the gap is provided at the center of the drill shank, and the diameter of the water injection hole is slightly larger than the size of the gap.

[0011] Preferably, the connection part between the wing body and the drill shank is provided with an arcuate slag discharge groove arranged along the length direction of the drill bit, and the columnar blade is located directly above the arcuate slag discharge groove, so that the waste slag cut out by the columnar blade can enter the arcuate slag discharge groove in time and be discharged from the drill bit.

[0012] Preferably, the connecting portion of the wing body and the drill shank is provided with an annular slag discharge groove along the circumferential direction of the drill bit, and the annular slag discharge groove is an arc-shaped annular slag discharge groove, and the arc-shaped slag discharge groove extends into the annular slag discharge groove, and the combined slag discharge has a better effect.

[0013] Preferably, a docking blind hole is provided inside the drill shank, the blind hole extends upward to below the annular slag discharge groove, and an internal thread is provided on the side of the docking blind hole.

[0014] Preferably, an external thread is provided on the outer side surface of the drill shank, and an annular limit platform is provided on the upper part of the drill shank, and the annular limit platform is located between the external thread and the annular slag discharge groove.

[0015] The beneficial technical effect of the present invention is that the inner seat body and the cylindrical blade on the inner seat body of the present invention have wing bodies protruding in the middle, which can first form a drill hole with a smaller aperture in the center during screw-in cutting, and then use the outer seat body and the cylindrical blade on the outer seat body to screw-in cutting to expand the aperture, which can produce a step-by-step rotary cutting drilling effect, realize the larger screw-in cutting area and cutting force decomposition of the existing single cylindrical blade, avoid the phenomenon that the cylindrical blade is easily worn or falls off quickly, and effectively improve the service life of the drill bit and the cutting and drilling efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic diagram of the three-dimensional structure of the drill bit; Figure 2 yes Figure 1A schematic diagram of a top view structure; Figure 3 yes Figure 2 AA section structural diagram; Figure 4 It is a schematic diagram of the main structure of the drill bit; Figure 5 yes Figure 4 A schematic diagram of a structure in which a cylindrical blade is adjusted to a vertical state; Figure 6 is a schematic diagram of the side view structure of the drill bit; Figure 7 It is a schematic diagram of the three-dimensional structure of the drill bit removing the columnar blade; Figure 8 It is a three-dimensional structural schematic diagram of another drill shank structure of the drill bit.

[0017] In the figure, 01. drill handle, 11. water injection hole, 12. blind hole, 13. internal thread, 14. external thread, 15. annular limit platform, 16. clamping plane, 02. drill base, 2. wing body, 21. inner seat body, 22. outer seat body, 23. circular groove, 24. cylindrical blade, 25. arc transition groove, 31. arc slag discharge groove, 32. annular slag discharge groove. DETAILED DESCRIPTION

[0018] Example 1, see the attached specification Figure 1-8 , a stepped anchor drill bit, comprising an integrally formed drill shank 01 and a drill base 02, the integrally formed drill shank 01 and drill base 02 make the overall strength of the drill bit higher, the drill base 02 comprises at least two wing bodies 2 spirally arranged with the drill bit axis as the center, the outer side surfaces of the wing bodies are located on the same cylindrical surface, the diameter of the wing body 2 is larger than the diameter of the drill shank 01, and at least two seat bodies are spirally arranged with the drill bit axis as the center on the upper part of the wing body 2, the heights of these seat bodies decrease in a step-like manner from the inside to the outside, and these seat bodies protrude in sequence from the center to the outside to form a multi-stage cutting structure, forming a drilling effect of drilling first and then expanding the hole, a circular groove 23 is provided on the inner end surface of the seat body, a columnar blade 24 is matched and installed in the circular groove 23, the sides of adjacent columnar blades 24 are arranged in contact with each other, the columnar blade 24 is a polycrystalline diamond composite sheet, the depth of the circular groove 23 is the same as the thickness of the columnar blade 24, to ensure the firmness of the installation and fixation of the columnar blade 24.

[0019] like Figure 3 and Figure 8 As shown, a docking blind hole 12 is provided inside the drill shank 01, and an internal thread 13 is provided on the side of the docking blind hole, and docking fixation can be achieved by sleeve-fitting the drill rod of the drilling rig through the blind hole and the internal thread 13. Alternatively, an external thread 14 is provided on the outer side of the drill shank 01, and an annular stopper 15 is provided on the upper part of the drill shank 01, and docking fixation can be achieved by sleeve-fitting the drill rod of the drilling rig through the external thread 14.

[0020] The surface of the protruding part of the seat body is an arc-shaped surface, which is coplanar with the cylindrical surface of the columnar blade 24, and an arc-shaped transition groove 25 is provided between the arc-shaped surfaces of adjacent seat bodies. The coplanar design of the seat body and the columnar blade 24 and the design of the arc-shaped transition groove 25 are both used to reduce the resistance of rotary cutting and improve the drilling effect of the drill bit. At the same time, the arc-shaped transition groove 25 also has a slag removal function.

[0021] There is a gap between adjacent wings 2, and a water injection hole 11 penetrating to the gap is provided at the center of the drill shank 01. Cooling water enters the gap through the water injection hole 11 and then flows into the columnar blade 24 for cooling.

[0022] Example 2, see the attached specification Figure 1-2 Based on the first embodiment, this embodiment designs two seats on the wing body 2, namely an inner seat 21 and an outer seat 22. The two inner and outer seats can meet the drilling effect of two-stage step cutting while being easy to process. It is a preferred embodiment of the present invention. The inner side surface of the inner seat 21 and the inner side surface of the wing body 2 are located in the same plane, and the outer side surface of the outer seat 22 and the outer side surface of the wing body 2 are located in the same cylindrical surface.

[0023] The diameter of the columnar blade 24 is 5-10mm and the thickness is 2-5mm. The diameter of the columnar blade 24 on the existing anchor drill bit is usually about 13mm and the thickness is about 5mm. The size design of the columnar blade 24 of this embodiment decomposes the existing columnar blade 24, reduces the large one into a small one, and reduces one into two, thereby reducing the force area and cutting resistance of a single columnar blade 24. In particular, the first pair of columnar blades in the center can quickly break into the cut rock and provide orientation and guidance for the feeding of the second pair of columnar blades on the outside.

[0024] The vertical distance between two adjacent groups of columnar blades 24 is D1, which is about 5 mm. The horizontal vertical distance between two columnar blades 24 is D2, which is about 7 mm. The height difference formed by D1 and D2 and the optimized position design can further improve the step-by-step cutting effect of the columnar blades 24.

[0025] When the drill bit of this embodiment is working: ① the drilling rig transmits power to the anchor drill bit through the drill rod, and the anchor drill bit rotates into the foundation; ② the inner seat body 21 in the middle of the anchor drill bit and the columnar blade 24 on the inner seat body 21 protrude the wing body 2 in the middle, and first contact the foundation when screwing in and cutting, and form a drill hole with a smaller aperture in the center; ③ then the outer seat body 22 and the columnar blade on the outer seat body 22 are screwed in and cut to expand the aperture to meet the aperture requirements of the anchor drilling hole, and the anchor hole is drilled in a step-by-step rotation and cutting manner; ④ during the drilling process, adjacent columnar blades 24 can share the cutting force and cutting area with each other, reduce their respective wear rates, avoid the phenomenon of rapid falling off of the columnar blades, and improve the service life of the drill bit and the cutting and drilling efficiency.

[0026] Example 3, see the attached specification Figure 1 , 4 The connecting part of the wing body 2 and the drill shank 01 is provided with an arc-shaped slag discharge groove 31 arranged along the length direction of the drill bit, and the columnar blade 24 is located directly above the arc-shaped slag discharge groove 31. The slag generated after cutting by the columnar blade 24 can be discharged from the arc-shaped slag discharge groove in time to ensure the cutting and drilling effect, and an annular slag discharge groove 32 is provided at the connecting part of the wing body 2 and the drill shank 01 along the circumferential direction of the drill bit. The arc-shaped slag discharge groove 31 extends into the annular slag discharge groove 32, and the slag discharged from the arc-shaped slag discharge groove can enter the annular slag discharge groove 32, further improving the chip removal effect.

Claims

1. A stepped anchor drill bit, characterized by: The drill bit base comprises an integrally formed drill shank and a drill bit base, wherein the drill bit base comprises at least two wing bodies which are spirally arranged with the drill bit axis as the center, the outer side surfaces of the wing bodies are located on the same cylindrical surface, at least two seat bodies are spirally arranged with the drill bit axis as the center on the upper part of the wing bodies, the heights of these seat bodies decrease in a step-like manner from the inside to the outside, a circular groove is provided on the inner end surface of the seat body, a columnar blade is matched and installed in the circular groove, and the side surfaces of adjacent columnar blades are arranged to fit each other.

2. The stepped anchor drill bit according to claim 1, characterized in that: The seat body on the wing body is provided with two, namely an inner seat body and an outer seat body, the inner side surface of the inner seat body and the inner side surface of the wing body are located in the same plane, and the outer side surface of the outer seat body and the outer side surface of the wing body are located in the same cylindrical surface.

3. The stepped anchor drill bit according to claim 2, characterized in that: The columnar blade has a diameter of 5-10 mm and a thickness of 2-5 mm.

4. The stepped anchor drill bit according to claim 1, characterized in that: The surface of the protruding portion of the seat body is an arc-shaped surface, and the arc-shaped surface is coplanar with the cylindrical surface of the columnar blade.

5. The stepped anchor drill bit according to claim 4, characterized in that: An arc-shaped transition groove is arranged between the arc-shaped surfaces of adjacent seat bodies.

6. The stepped anchor drill bit according to claim 1, characterized in that: A gap is arranged between adjacent wing bodies, and a water injection hole penetrating to the gap is arranged at the center of the drill handle.

7. The stepped anchor drill bit according to claim 1, characterized in that: The connecting part of the wing body and the drill handle is provided with an arc-shaped slag discharge groove arranged along the length direction of the drill bit, and the columnar blade is located directly above the arc-shaped slag discharge groove.

8. The stepped anchor drill bit according to claim 7, characterized in that: The connecting part of the wing body and the drill shank is provided with an annular slag discharge groove along the circumferential direction of the drill bit, and the arc-shaped slag discharge groove extends into the annular slag discharge groove.

9. The stepped anchor drill bit according to claim 1, characterized in that: A docking blind hole is arranged inside the drill handle, and an internal thread is arranged on the side of the docking blind hole.

10. The stepped anchor drill bit according to claim 1, characterized in that: The outer side surface of the drill handle is provided with an external thread, and an annular limiting platform is provided on the upper part of the drill handle.

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