Drill bit

Abstract

The utility model belongs to the field of impact type drill bits, and particularly provides a drill bit. The drill bit comprises a base body, a gauge tooth installation area is arranged on the edge of the front end of the base body, a plurality of gauge teeth are installed in the gauge tooth installation area, a boss located on the front side of the gauge tooth installation area and connected with the gauge tooth installation area is arranged in the center of the front end of the base body, a plurality of column teeth are installed on the boss, and all the column teeth are center teeth with the axes parallel to the axis of the base body. Due to the fact that the boss is connected with the gauge protection tooth installation area, in the radial direction, the gauge protection tooth and the center tooth on the boss are matched together, and rock breaking operation at different positions in the radial direction can still be completed. Meanwhile, due to the fact that the boss has a certain protruding height, the distance between the center teeth and the gauge protection teeth is long in the axial direction, more space is provided for forming the tooth holes, the problem that different tooth holes are prone to penetrating is solved, more and larger center teeth and gauge protection teeth can be conveniently installed, and the performance of the drill bit is improved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the field of percussion drill bit, especially, relate to a drill bit. BACKGROUND

[0002] The top hammer drill bit and the down-the-hole drill bit are the drilling tools commonly used in the fields of mine exploitation and tunnel excavation, which mainly break hard rock to form a borehole through impact and rotation.

[0003] The conventional down-the-hole drill bit can refer to the utility model patent with the authorized announcement number CN202194577U, specifically, the drill bit includes a base body (generally a steel base body), and a plurality of column teeth are installed at the front end of the base body. According to the installation positions and different functions of the column teeth, the column teeth can be divided into center teeth and gauge teeth, the center teeth are located at the central position of the front end of the drill bit, the axis of the center teeth is parallel to the axis of the drill bit, and the main function of the center teeth is to first contact and break rock during the drilling process; the gauge teeth are distributed at the outer edge part of the drill bit, the axis of the gauge teeth is at a set angle with the axis of the drill bit, and the main function of the gauge teeth is to maintain the consistency of the drilling diameter.

[0004] According to the different structures of the front end of the base body, as shown in Figure 1 and Figure 2 , the existing base body 1 can be divided into a planar base body ( Figure 1 ) and a convex base body ( Figure 2 ), the front end of the two base bodies 1 has a planar part and a conical part, the planar part is used for installing the center teeth and constitutes a center tooth installation area, and the conical part is used for installing the gauge teeth and constitutes a gauge tooth installation area. The center tooth installation area is provided with a tooth hole with a diameter smaller than that of the center teeth, the center teeth are correspondingly inserted into the tooth hole, and the axis of the tooth hole is parallel to the axis of the base body 1; the gauge tooth installation area is provided with a tooth hole with a diameter smaller than that of the gauge teeth, the gauge teeth are correspondingly inserted into the tooth hole, and the axis of the tooth hole is at a set angle with the axis of the base body 1. In addition, the two base bodies 1 are also provided with a slag discharge groove 102 and a flow guide structure 101 connected with the slag discharge groove 102 to facilitate slag discharge.

[0005] In order to improve the performance of the drill bit and adapt to different rock layers, a large number of center teeth and gauge teeth need to be arranged on the drill bit, the center teeth close to the edge position in the radial direction are close to the gauge teeth, at this time, the tooth hole for inserting the center teeth and the tooth hole for inserting the gauge teeth can be penetrated, and the teeth cannot be normally inserted. In other words, the current drill bit is difficult to arrange a large number of column teeth. TECHNICAL SOLUTION

[0006] The utility model aims at providing a drill bit to solve the technical problem that the current drill bit is difficult to arrange a large number of column teeth.

[0007] In order to achieve the above-mentioned purpose, the technical scheme of the drill bit provided by the utility model is as follows:

[0008] A drill bit comprises a base body, a front end edge of the base body is provided with a gauge leg mounting area, a plurality of gauge legs are mounted on the gauge leg mounting area, a boss is arranged at a front end center of the base body and located at a front side of the gauge leg mounting area and connected with the gauge leg mounting area, and a plurality of center teeth are mounted on the boss and all have axes parallel to an axis of the base body.

[0009] As a further improvement, the boss has a protruding height in the axial direction of no more than 20 mm.

[0010] As a further improvement, the boss has a cylindrical structure.

[0011] As a further improvement, the base body is provided with a slag discharge groove and an annular flow guide groove in communication with the slag discharge groove.

[0012] As a further improvement, a bottom surface of the flow guide groove is an arc-shaped surface opening outward.

[0013] As a further improvement, the gauge legs and the center teeth are all spherical teeth.

[0014] As a further improvement, the gauge legs and the center teeth are all polycrystalline diamond teeth.

[0015] The utility model belongs to an improved invention, and has the beneficial effects that: unlike the prior art, the drill bit in the utility model has a boss specially used for mounting center teeth at a front end center position, because the boss is connected with the gauge leg mounting area, the gauge legs and the center teeth on the boss can still jointly complete rock breaking operations at different positions in the radial direction. Meanwhile, because the boss has a certain protruding height, the center teeth and the gauge legs are far apart in the axial direction, so there is more space for opening tooth holes, the problem of easy penetration of different tooth holes is solved, and more and larger center teeth and gauge legs are conveniently installed, and the performance of the drill bit is improved. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 FIG. 1 is a structural schematic view of a planar drill bit base body in the prior art;

[0017] Figure 2 FIG. 2 is a structural schematic view of a convex drill bit base body in the prior art;

[0018] Figure 3 FIG. 3 is an axonometric view of a drill bit embodiment in the utility model;

[0019] Figure 4 FIG. 4 is a front view of the drill bit embodiment in the utility model.

[0020] BRIEF DESCRIPTION OF THE DRAWINGS

[0021] 1, base body; 2, center teeth; 3, gage teeth; 101, flow guide structure; 102, slag discharge groove; 103, flow guide groove; 104, boss. DETAILED DESCRIPTION

[0022] To facilitate the installation of larger and more number of gage teeth and center teeth on the drill bit, the basic technical concept of the present application is to provide a boss on the base body for installing the center teeth, so as to increase the installation distance between the gage teeth and the center teeth in the axial direction without affecting the arrangement of the gage teeth and the center teeth in the radial direction, facilitate the arrangement of larger and more gage teeth and center teeth, and thus improve the performance of the drill bit.

[0023] Based on the above concept, the present application will be further described in detail in combination with different embodiments.

[0024] As a basic embodiment, as shown in Figure 3 and Figure 4 , the drill bit provided by the present embodiment can be a push drill bit, which comprises a base body 1. Except for the front end structure, the structure of other parts of the base body 1 can be consistent with the prior art, for example, the base body 1 is also provided with a slag discharge groove 102. The front end edge of the base body 1 is provided with a gage tooth installation area, and a plurality of gage teeth 3 are installed on the gage tooth installation area. The gage teeth 3 and the axis of the base body 1 are at a set angle, and the number of the gage teeth 3 and the angle between the gage teeth 3 and the axis of the base body 1 are not specifically limited here, and can be flexibly set by the person skilled in the art according to the actual drilling needs. Specifically, the front end edge of the base body 1 can be provided with a conical surface structure as shown in Figure 3 and Figure 4 , and each gage tooth 3 is circumferentially spaced apart at the conical surface structure.

[0025] In order to install the center teeth 2, as shown in Figure 3 and Figure 4 , the front end center of the base body 1 is also provided with a boss 104 located on the front side of the gage tooth installation area, and the boss 104 is connected with the gage tooth installation area. A plurality of column teeth are installed on the boss 104, and similarly, the number of the column teeth is not specifically limited here. It should be emphasized that each column tooth installed on the boss 104 is a center tooth 2, that is, all the column teeth installed on the boss 104 are parallel to the axis of the base body 1.

[0026] From the analysis of the above structure, in the present embodiment, since the boss 104 is connected with the gage tooth installation area, in the radial direction, the gage teeth 3 and the center teeth 2 on the boss 104 can still complete the rock breaking operation at different positions in the radial direction. At the same time, since the boss 104 has a certain protrusion height, in the axial direction, the center teeth 2 and the gage teeth 3 are far apart, so there is more space to open the tooth hole, which solves the problem of easy penetration of different tooth holes, and thus facilitates the installation of more and larger center teeth 2 and gage teeth 3, and improves the performance of the drill bit.

[0027] To ensure that the center tooth 2 and the gauge tooth 3 can break rock essentially simultaneously, the axial protrusion height of the boss 104 should not be too large. In some optional embodiments, the axial protrusion height of the boss 104 is no greater than 20mm. For example, the protrusion height can be 20mm, 18mm, 15mm, etc. Within this range, while ensuring the normal installation of the center tooth 2, the boss 104 will not be too high, ensuring synchronous drilling and also giving the boss 104 high strength.

[0028] To ensure that there is more space on the boss 104 to install the center tooth 2, in some preferred embodiments, such as Figure 4 As shown, the boss 104 has a cylindrical structure. Compared with the frustum-shaped boss 104, this boss 104 has equal diameters at both ends along the axis and a larger front face area, which provides more space for mounting the center tooth 2.

[0029] like Figure 3 and Figure 4 As shown, optionally, both the diameter-maintaining tooth 3 and the center tooth 2 are spherical teeth. Compared with planar teeth or conical teeth, spherical teeth can concentrate the impact force and increase the contact pressure at each contact point. At the same time, they are less prone to drill cuttings accumulation.

[0030] In addition, the diameter-maintaining tooth 3 and the center tooth 2 can be made of polycrystalline diamond (i.e., polycrystalline diamond composite sheet). Compared with cemented carbide teeth or PCBN composite sheets, polycrystalline diamond teeth have higher hardness and are suitable for use in harder rock formations.

[0031] Furthermore, considering the efficiency of slag removal, in some preferred embodiments, the substrate 1 is provided with an annular guide groove 103 communicating with the slag removal trough 102. Compared with the prior art ( Figure 1 , Figure 2 Compared to the smooth transition structure used as the flow guide structure 101, the diameter of the flow guide groove 103 is smaller, which is equivalent to setting an inwardly concave diameter reduction section at the front end of the base 1. This provides more space for the rock slag to flow outward, and at the same time, it is easier to process a deeper slag discharge groove 102 in the radial direction, thus facilitating slag discharge.

[0032] Even better, such as Figure 4 As shown, the bottom surface of the guide channel 103 is an outward-facing arc-shaped surface. Compared with a non-arc-shaped bottom surface (such as a trapezoidal surface), the arc-shaped surface can ensure that the slag can flow more smoothly and avoid rapid wear caused by concentrated stress in local areas, thereby improving the service life of the substrate 1.

[0033] Finally, it needs to be explained that the above is only the preferred embodiment of the present application, and is not used to limit the present application, although the present application is described in detail with reference to the foregoing embodiments, for those skilled in the art, it still can modify the technical solutions recorded in the foregoing embodiments without paying creative labor, or make equivalent replacement for part of the technical features. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A drill bit comprising a body having a front end edge provided with a gage tooth mounting area, the gage tooth mounting area mounting a plurality of gage teeth, characterised in that, The front end center of the base body is provided with a boss located in front of the gage tooth mounting area and connected with the gage tooth mounting area, and a plurality of column teeth are mounted on the boss, and all the column teeth are central teeth with axes parallel to the axis of the base body.

2. The drill bit of claim 1 wherein, The protruding height of the boss in the axial direction is not greater than 20 mm.

3. The drill bit of claim 1 wherein, The boss is in a cylindrical structure.

4. The drill bit of claim 1 or 2 or 3, wherein, The base body is provided with a slag discharge groove and an annular flow guide groove in communication with the slag discharge groove.

5. The drill bit of claim 4 wherein, The groove bottom surface of the flow guide groove is an arc surface with an opening outward.

6. The drill bit of claims 1, 2 or 3 wherein, The gage teeth and the central teeth are all spherical teeth.

7. The drill bit of claims 1, 2 or 3, wherein, The gage teeth and the central teeth are all polycrystalline diamond teeth.

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