Drill bit structure

Abstract

The utility model belongs to the technical field of drill bits, and particularly relates to a drill bit structure. The drill bit structure comprises a groove front cutter face. The chisel edge thinning part is arranged on one side of the groove front cutter face, and the chisel edge thinning part is in a V shape; wherein a lug boss is arranged at the bottom of the chisel edge thinning part. The convex part reduces the curled radius of cuttings at the part, so that the generation of built-up edges of the inner straight blade in the drilling process is reduced; the contact area of cuttings and the cutter body in the discharging process is reduced, and the cutting temperature is effectively reduced.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of drill bit, concretely relates to a drill bit structure. BACKGROUND

[0002] The thinning of the chisel edge of the drill bit refers to the general whole carbide alloy, in the end face cutting edge part, in addition to the cutting edge produced by the slotting, the part close to the center of the drill tip, the part that the core thickness of the drill tip is thinned to a sharp, such as shown in the figure. Figure 1

[0003] The chisel edge part of the carbide drill bit is often the source of the main cutting resistance in the cutting process of the drill bit, and the thinning of the chisel edge can effectively reduce the length of the chisel edge of the drill bit and reduce the cutting resistance. Figure 2 However, since the V-shaped structure is suddenly forced to be sharply folded in the cutting process, the cutting radius is small, and the cutting load is greatly increased; the severe deformation of the cutting chip also increases the cutting temperature of this part, thereby reducing the service life of the tool. TECHNICAL PROBLEM

[0004] The utility model aims at providing a drill bit structure to solve the above technical problems.

[0005] In order to solve the above technical problems, the utility model provides a drill bit structure, which comprises:

[0006] A chisel land is arranged on one side of the chisel land.

[0007] A chisel edge thinning part is arranged on one side of the chisel land, and the chisel edge thinning part is V-shaped.

[0008] A protruding part is arranged at the bottom of the chisel edge thinning part.

[0009] In an embodiment of the present application, the protruding part is arc-shaped.

[0010] In an embodiment of the present application, the length of the protruding part accounts for half of the total length L of the chisel edge thinning part.

[0011] The drill bit structure of the utility model comprises a chisel land, a chisel edge thinning part arranged on one side of the chisel land, and a protruding part arranged at the bottom of the chisel edge thinning part. The protruding part reduces the radius of the curling of the cutting chip at this part, reduces the generation of the built-up edge of the inner chisel edge in the drilling process, reduces the contact area of the cutting chip with the tool body in the discharging process, and effectively reduces the cutting temperature.

[0012] ​The other features and advantages of the present application will be described in the following description and, in part, will become apparent to those skilled in the art upon examination of the following or can be learned by practice of the present application. The purposes and other advantages of the present application can be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

[0013] To make the above objectives, features and advantages of the present application more apparent, the following preferred embodiments are specifically described, and the accompanying drawings are referred to, and the detailed description is as follows. BRIEF DESCRIPTION OF DRAWINGS

[0014] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or the prior art description. Obviously, the drawings described below are some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0015] Figure 1 is the position of the thinning part of the cross blade in the prior art drill bit structure;

[0016] Figure 2 is a working schematic diagram of the thinning part of the cross blade in the prior art drill bit structure;

[0017] Figure 3 is a schematic diagram of the preferred embodiment of the drill bit structure of the present application;

[0018] Figure 4 is a length schematic diagram of the protruding part and the thinning part of the cross blade of the drill bit structure of the present application;

[0019] Figure 5 is a schematic diagram of the drill bit structure of the present application;

[0020] Figure 6 is a working schematic diagram of the thinning part of the cross blade of the drill bit structure of the present application. DETAILED DESCRIPTION

[0021] In order to make the objectives, technical solutions and advantages of the embodiments of the present application more apparent, the technical solutions of the present application will be described clearly and completely with reference to the drawings. Obviously, the described embodiments are only some embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0022] Glossary:

[0023] Inner straight edge of drill bit: refers to the cutting edge of the thinning part of the cross blade participating in cutting.

[0024] Backlash angle: The angle formed between the thinned portion of the chisel edge and the drill bit axis.

[0025] Thinning rake angle: The angle formed between the rake face of the drill tip cutting edge and the drill axis.

[0026] Numroto Plus software: a widely used five-axis CNC software for grinding machines, with rich features and a high degree of programming freedom.

[0027] See Figure 3 and Figure 6 In one embodiment of this application, the drill bit structure includes: a groove front face; a transverse cutting edge thinning portion disposed on one side of the groove front face, the transverse cutting edge thinning portion being V-shaped; wherein a protrusion is provided at the bottom of the transverse cutting edge thinning portion.

[0028] Optionally, the protrusion is arc-shaped.

[0029] Preferred, see Figure 4 The length of the protrusion is half of the total length L of the thinning portion of the transverse blade.

[0030] In one optional drill bit structure fabrication process, NUMroto PLUS CNC software can be used to modify the path of the grinding wheel on the thinned chisel edge, so that a raised point is formed at the bottom of the corner groove. The specific operation is as follows:

[0031] During the grinding process, a relatively small dressing rake angle β1 (-2° to -5°) is applied near the center of the drill tip. Figure 5 The tooth gap angle of this part ( Figure 4 The α1 is set to 28°–35°, and then the cutting rake angle β2 is gradually increased to (10°–14°) in the direction towards the outer periphery, increasing the backlash angle ( Figure 4 α2) to 55°~65°; During the grinding process, due to the change in angle, a circular protrusion will be formed at the bottom of the original V-shaped tooth gap. The length of the protrusion is about half of the total length L of the thinning part of the transverse cutting edge.

[0032] In one application scenario, the drill bit structure of this embodiment was used to perform high-speed drilling tests on 42CrMo material (diameter 12.5: Vc150, f0.4). Compared with the traditional transverse cutting structure, it effectively extended the service life (the drilling life of the ordinary structure is 45 meters, while the test structure has a life of 68 meters, which is a 51% increase in service life).

[0033] In summary, the drill bit structure of this utility model has the following advantages:

[0034] 1. The radius of the curling of the chip in this part is slowed down, and the build-up of the chip in the inner straight land is reduced during the drilling process;

[0035] 2. The convex structure reduces the contact area of the chip with the tool body during the discharge process (such as Figure 6 ), effectively reducing the cutting temperature;

[0036] 3. Due to the use of a variable (gradually increasing) inner straight land rake angle, the cutting edge of the inner straight land is sharp, the cutting in the drilling process is good, the cutting temperature is low, the cutting load is also reduced, and the service life of the tool can be effectively prolonged;

[0037] 4. It is particularly suitable for some high-speed drilling scenarios.

[0038] Each device (parts not described in detail) selected in the present application is a general standard part or a part known to those skilled in the art, and its structure and principle can be known by the skilled person through a technical manual or through a conventional experimental method.

[0039] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting" should be understood in a broad sense, for example, it can be fixedly connected, It can also be detachably connected, or integrally connected

[0040] Based on the above ideal embodiments according to the present application, through the above description, relevant personnel can make various changes and modifications without deviating from the technical idea of the present application. The technical scope of the present application is not limited to the contents in the specification, and the technical scope must be determined according to the scope of the claims.

Claims

1. A drill bit structure, characterized by, Comprise: a flute rake face; a land thinning portion provided on one side of the flute rake face, the land thinning portion being V-shaped; wherein a protrusion is provided at the bottom of the land thinning portion.

2. The drill bit structure according to claim 1, wherein the protrusion is circular arc-shaped.

3. The drill bit structure according to claim 1, wherein the length of the protrusion accounts for half of the total length L of the land thinning portion.

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