A drill bit

Abstract

The present application proposes a drill bit, comprising a drill body, wherein the mounting end of the drill body is provided with a first passage extending therethrough, and the top of the drill body is provided with a mounting groove for mounting a blade connected to the first passage, and the blade has a mounting hole. The drill bit also includes a locking mechanism extending through the first passage and the mounting hole. When the locking mechanism passes through the first passage and the mounting hole to lock the blade, the locking mechanism applies a first downward force and a second downward force to a first force-bearing portion and a second force-bearing portion on both sides of the bottom of the inner wall of the mounting hole of the blade, the first force and the second force being symmetrical about the centerline of the blade perpendicular to the first direction. Compared with the prior art, the present application applies symmetrical forces to both ends of the blade, resulting in balanced forces, avoiding damage to the blade and increasing the blade's service life.

Description

Technical Field

[0001] The present application relates to the field of cutting technology, and in particular to a drill bit. Background Art

[0002] In recent years, hole machining tools, especially carbide drills, have developed rapidly. To achieve high efficiency, low cost, and save carbide materials, new replaceable head drills have emerged. The top of the replaceable head drill has a slot for inserting the insert, and the insert has a through hole.

[0003] The existing method of locking the blade is to open a single-sided tapered hole on the hole slot that is connected to the hole slot, and pass a bolt eccentrically arranged with the tapered hole through the through hole on the blade and be threadedly connected with the tapered hole to lock the blade; since the bolt is eccentrically arranged with the tapered hole, the tapered hole exerts downward pressure on the blade. Therefore, in the process of locking the blade by the bolt, the blade close to the tapered hole is subjected to greater force, and the hardness of the blade is very high. In the case of uneven force, it is easy to break, posing a major safety hazard. Summary of the Invention

[0004] In view of the above-mentioned defects or deficiencies in the prior art, the present application aims to provide a drill bit, comprising:

[0005] A drill body, wherein a mounting end of the drill body is provided with a first passage extending in a first direction, a mounting groove for inserting a blade is provided perpendicularly and through the first passage; the blade has a mounting hole extending in the first direction; a locking mechanism passing through the first passage and the mounting hole locks the blade to the drill body;

[0006] The bottom of the inner wall of the installation hole of the blade and the parts arranged along the first direction are respectively a first force-bearing part and a second force-bearing part;

[0007] In the process of locking the blade through the first channel and the mounting hole, the locking mechanism simultaneously applies a first force to the first force-bearing part and a second force to the second force-bearing part; the first force and the second force are symmetrical about the center line of the blade perpendicular to the first direction.

[0008] According to the technical solution provided in the embodiment of the present application, the first channel includes a main channel arranged in the middle and conical channels symmetrically arranged on both sides of the main channel along the first direction. The axis of the first channel is the first axis, the axis of the locking mechanism is the second axis, and the first axis is located on the side of the second axis away from the installation end.

[0009] According to the technical solution provided in the embodiment of the present application, the locking mechanism includes a first locking component and a second locking component, the first locking component includes a first conical portion and a first connecting portion distributed along the first direction; the second locking component includes a second conical portion and a second connecting portion distributed along the first direction; the first connecting portion has a first space therein, the first connecting portion passes through the mounting hole, and the second connecting portion is placed in the first space and connected to the first connecting portion; the first conical portion is threadedly connected to the inner wall of the conical channel close to the mounting end side, and the second conical portion is threadedly connected to the inner wall of the other conical channel close to the mounting end side.

[0010] According to the technical solution provided in the embodiment of the present application, the inner wall of the first connecting part is provided with an internal thread, and the outer wall of the second connecting part is provided with an external thread matching the internal thread.

[0011] According to the technical solution provided in the embodiment of the present application, along the first direction, the length of the first connecting portion is greater than or equal to the length of the mounting hole.

[0012] According to the technical solution provided in the embodiment of the present application, the locking mechanism includes: a third locking assembly and a fourth locking assembly;

[0013] The third locking assembly includes a third tapered portion and a third connecting portion distributed along the first direction, the third connecting portion passes through the mounting hole, and the third tapered portion is threadedly connected to the inner wall of the tapered channel near the mounting end; the third connecting portion is coaxially provided with a fourth connecting portion on a side away from the third tapered portion;

[0014] The fourth locking assembly includes a fourth tapered portion disposed in the tapered passage on a side away from the third locking assembly, the fourth tapered portion being coaxial with the third tapered portion, a second through hole being defined in a middle portion of the fourth tapered portion, a linkage assembly being defined on a side of the fourth tapered portion away from the third locking assembly, and the fourth connecting portion passing through the second through hole and abutting against the linkage assembly;

[0015] When the third locking assembly rotates toward the threaded side of the fourth locking assembly, the linkage assembly applies a pushing force to the fourth conical portion along the first direction toward the third locking assembly side, and the conical channel applies a third force perpendicular to the first direction and toward away from the mounting end side to the second force-bearing portion.

[0016] According to the technical solution provided in the embodiment of the present application, the linkage component includes:

[0017] The linkage component includes:

[0018] Two connecting structures are symmetrically arranged about the axis of the fourth tapered portion, each of the connecting structures comprising: a first connecting rod, a second connecting rod, and a third connecting rod, each of which is hinged at one end, wherein the hinge axis is a first hinge axis, the axis direction of the first hinge axis is a second direction, and the second direction is perpendicular to the first direction; the first connecting rod is connected to the fourth tapered portion away from the first hinge axis end; the third connecting rod is hinged to the drill body away from the first hinge axis end;

[0019] The linkage component also includes:

[0020] An abutment member is hinged to the two second connecting rods at a side close to the fourth tapered portion and away from the first connecting rod ends; and the fourth connecting portion abuts against the abutment member at a side close to the second connecting rod.

[0021] According to the technical solution provided in the embodiment of the present application, the edge of the mounting hole away from the mounting end is placed in the first channel.

[0022] According to the technical solution provided in an embodiment of the present application, the first connecting portion is threadedly connected to the inner wall of the main channel.

[0023] According to the technical solution provided in the embodiment of the present application, the third connecting portion is threadedly connected to the inner wall of the main channel.

[0024] In summary, the present application proposes a drill bit, comprising a drill body, wherein the mounting end of the drill body is provided with a through first channel, the top of the drill body is provided with a mounting groove for mounting a blade connected to the first channel, and the blade has a mounting hole; the drill bit also includes a locking mechanism that passes through the first channel and the mounting hole; when the locking mechanism passes through the first channel and the mounting hole to lock the blade, the locking mechanism applies a first downward force and a second downward force to the first force-bearing portion and the second force-bearing portion on both sides of the bottom of the inner wall of the mounting hole of the blade, and the first force and the second force are symmetrical about the center line of the blade perpendicular to the first direction. Compared with the prior art, the present application applies symmetrical forces to both ends of the blade, resulting in balanced forces, avoiding damage to the blade and increasing the service life of the blade. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is an exploded view of the structure of a drill bit provided in Example 1 of the present application;

[0026] Figure 2 A structural schematic diagram of a drill bit provided in Example 1 of the present application;

[0027] Figure 3 This is a schematic structural diagram of a drill bit provided in Example 2 of the present application.

[0028] 1. Blade; 11. First force-bearing part; 12. Second force-bearing part; 2. Drill body; 21. Mounting end; 3. First channel; 31. Main channel; 32. Conical channel; 33. First axis; 4. Locking mechanism; 41. Second axis; 42. First gap; 43. First locking assembly; 431. First conical portion; 432. First connecting portion; 433. First space; 434. Second gap; 44. Second locking assembly; 441. Second conical portion; 442. Second connecting portion; 443. Third gap; 45. Third locking assembly; 451. Third conical portion; 452. Third connecting portion; 453. Fourth connecting portion; 46. Fourth locking assembly; 461. Fourth conical portion; 462. Fourth gap; 463. First connecting rod; 464. Second connecting rod; 465. Third connecting rod; 466. Abutment DETAILED DESCRIPTION

[0029] The present application will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the relevant invention and are not intended to limit the invention. It should also be noted that, for ease of description, only the portions relevant to the invention are shown in the accompanying drawings.

[0030] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0031] Example 1

[0032] As mentioned in the background technology, in order to solve the problems in the prior art, the present application proposes a drill bit, which includes:

[0033] A drill body 2, wherein a mounting end 21 of the drill body 2 is provided with a first passage 3 extending in a first direction, a mounting groove for inserting a blade 1 is arranged perpendicularly and through the first passage 3; the blade 1 has a mounting hole extending in the first direction; a locking mechanism 4 passing through the first passage 3 and the mounting hole locks the blade 1 on the drill body 2;

[0034] The bottom of the inner wall of the mounting hole of the blade 1 and the parts arranged along the first direction are respectively a first force-bearing portion 11 and a second force-bearing portion 12;

[0035] In the process of passing through the first channel 3 and the mounting hole to lock the blade 1, the locking mechanism 4 simultaneously applies a first force to the first force-bearing part 11 and a second force to the second force-bearing part 12; the first force and the second force are symmetrical about the center line of the blade 1 perpendicular to the first direction.

[0036] Among them, please refer to Figure 1As shown, the first direction is the horizontal direction, the mounting end 21 is the top of the drill body 2, the first force-bearing portion 11 and the second force-bearing portion 12 are respectively located on the left and right sides of the bottom of the inner wall of the first through hole. Optionally, the middle part of the blade 1 is cylindrical, and the center line of the blade 1 perpendicular to the first direction is the axis of the blade 1. The present application applies symmetrical forces on the left and right ends of the blade 1. Compared with the prior art that only applies downward pressure on one side, the force is balanced, damage to the blade 1 is avoided, and the service life of the blade 1 is increased.

[0037] In a preferred embodiment, the first channel 3 includes a main channel 31 located in the middle and tapered channels 32 symmetrically located on both sides of the main channel 31 along the first direction. The axis of the first channel 3 is the first axis 33, and the axis of the locking mechanism 4 is the second axis 41. The first axis 33 is located on the side of the second axis 41 away from the mounting end 21.

[0038] Please refer to Figure 1 As shown, in certain specific scenarios, when the locking mechanism 4 passes through the mounting hole, the outer wall of the locking mechanism 4 is in close contact with the inner wall of the mounting hole, the two are coaxially arranged, and are eccentrically arranged with respect to the first channel 3.

[0039] In addition, the edge of the mounting hole away from the mounting end 21 is located in the first channel 3 .

[0040] Please refer to Figure 1 As shown, the lower end of the mounting hole is placed in the first channel 3, that is, a first gap 42 is formed between the bottom side of the locking mechanism 4 and the inner wall of the first channel 3, so that the locking mechanism 4 can contact the bottom of the inner wall of the mounting hole to form the first force-bearing part 11 and the second force-bearing part 12, and then the first force and the second force can be applied to the first force-bearing part 11 and the second force-bearing part 12.

[0041] In a preferred embodiment, the locking mechanism 4 includes a first locking component 43 and a second locking component 44, the first locking component 43 includes a first conical portion 431 and a first connecting portion 432 distributed along the first direction; the second locking component 44 includes a second conical portion 441 and a second connecting portion 442 distributed along the first direction; the first connecting portion 432 has a first space 433, the first connecting portion 432 passes through the mounting hole, and the second connecting portion 442 is placed in the first space 433 and connected to the first connecting portion 432; the first conical portion 431 is threadedly connected to the inner wall of the conical channel 32 close to the mounting end 21 side, and the second conical portion 441 is threadedly connected to the inner wall of the other conical channel 32 close to the mounting end 21 side.

[0042] Please refer to Figure 1 and Figure 2 As shown, the first tapered portion 431 and the second tapered portion 441 have a first internal thread inside, and the first tapered portion 431 and the second tapered portion 441 have the same structure. The first locking assembly 41 is inserted into the first channel 3 from the tapered channel 32 on the left, and the first connecting portion 432 passes through the mounting hole. The outer wall of the first tapered portion 431 is provided with a first external thread matching the first internal thread. When the first tapered portion 431 is rotated to lock the blade 1, due to the eccentric arrangement of the first channel 3 and the locking mechanism 4, a second gap 434 is formed between the bottom of the first tapered portion 431 and the inner wall of the first channel 3, and the top of the first tapered portion 431 generates an extrusion force on the top of the tapered channel 32. The top of the tapered channel 32 applies a reverse downward pressure to the first tapered portion 431, and the first connecting portion 432 connected to the first tapered portion 431 contacts the first force-bearing portion 11, so it applies a downward first force to the first force-bearing portion 11.

[0043] The second conical portion 441 and the first conical portion 431 are symmetrically arranged with respect to the axis of the mounting groove. The second locking assembly 44 is inserted into the first channel 3 from the right conical channel 32, and the second connecting portion 442 is connected to the first connecting portion 432. The inner wall of the conical channel 32 on the right is provided with a second internal thread having the same pitch as the first internal thread and the opposite direction of rotation. The outer wall of the second conical portion 441 is provided with a second external thread matching the second internal thread. Since the first channel 3 and the locking mechanism 4 are eccentrically arranged, the bottom of the second conical portion 442 and the conical channel 3 are eccentric. 2; the second conical portion 441 is threadedly connected to the conical channel 21. When the second conical portion 441 is rotated, the top of the second conical portion 441 generates an extrusion force on the top of the conical channel 32 on the right side, and the top of the conical channel 32 applies a reverse downward pressure to the second conical portion 441, and the second connecting portion 442 connected to the second conical portion 441 is connected to the inner wall of the first connecting portion 432. The first connecting portion 432 contacts the second force-bearing portion 12, so a second downward force is applied to the second force-bearing portion 12.

[0044] Along the first direction, the length of the first connecting portion 432 is greater than or equal to the length of the mounting hole; Figure 1 and Figure 2As shown, since the second connecting portion 442 is placed in the first space 433, the outer diameter of the second connecting portion 442 is smaller than the inner diameter of the first connecting portion 432, so it is the first connecting portion 432 that is in direct contact with the blade 1. Therefore, if the length of the first connecting portion 432 is smaller than the length of the mounting hole, that is, when the first connecting portion 432 extends from the conical channel 32 on the left into the first channel 3, its right end can at least extend to the second force-bearing portion 12, then the first connecting portion 432 contacts the second force-bearing portion 12 and can apply a force to the second force-bearing portion 12; if the first connecting portion 432 does not extend to the second force-bearing portion 12, there will be a gap between the bottom end of the second connecting portion 442 and the second force-bearing portion 12, so no force can be applied to the second force-bearing portion 12.

[0045] In a preferred embodiment, an inner wall of the first connecting portion 432 is provided with an internal thread, and an outer wall of the second connecting portion 442 is provided with an external thread matching the internal thread.

[0046] Please refer to Figure 1 and Figure 2 As shown, the second connecting part 442 is placed in the first space 433 of the first connecting part 432. The second connecting part 442 needs to be connected to the first connecting part 432 so that the reverse force applied by the conical channel 32 to the second conical part 441 can be applied to the second force-bearing part 12 through the first connecting part 432. Therefore, the second connecting part 442 cannot be placed in the first space 433 in suspension; in certain specific scenarios, the first connecting part 432 and the second connecting part 442 are threadedly connected. In addition to applying the second force to the second force-bearing part 12 through the first connecting part 432, the threaded connection between the two can also further improve the locking stability of the blade 1.

[0047] Example 2

[0048] The same points as those in the embodiment will not be described in detail. The difference is that the locking mechanism 4 includes: a third locking assembly 45 and a fourth locking assembly 46;

[0049] The third locking assembly 45 includes a third tapered portion 451 and a third connecting portion 452 distributed along the first direction. The third connecting portion 452 passes through the mounting hole, and the third tapered portion 451 is threadedly connected to the inner wall of the tapered channel 32 near the mounting end 21. A fourth connecting portion 453 is coaxially provided on the side of the third connecting portion 452 away from the third tapered portion 451.

[0050] The fourth locking assembly 46 includes a fourth tapered portion 461 disposed in the tapered passage 32 on a side away from the third locking assembly 45. The fourth tapered portion 461 is coaxially arranged with the third tapered portion 451. A second through hole is defined in the middle of the fourth tapered portion 461. A linkage assembly is defined on the side of the fourth tapered portion 461 away from the third locking assembly 45. The fourth connecting portion 453 passes through the second through hole and abuts against the linkage assembly.

[0051] When the third locking assembly 45 is threadedly rotated toward the side of the fourth locking assembly 46, the linkage assembly applies a pushing force to the fourth conical portion 461 along the first direction toward the side of the third locking assembly 45, and the conical channel 32 applies a third force perpendicular to the first direction and toward the side away from the mounting end 21 to the second force-bearing portion 12.

[0052] Please refer to Figure 1-Figure 3 As shown, in this embodiment, the structure of the drill body 2 is the same as that of Example 1, and it also has a first channel 3. The structure of the third tapered portion 451 is the same as that of the first tapered portion 431 and the second tapered portion 441 in Example 1, and both are eccentrically arranged with respect to the first channel 3. Therefore, when the third tapered portion 451 is rotated, the tapered channel 32 will generate a downward force on the first force-bearing portion 11; the difference is that the interior of the third connecting portion 452 is a solid structure, and there is no first space 433 of the first connecting portion 432. The right side of the third connecting portion 452 is also connected to a fourth connecting portion 453 that passes through the second through hole for abutting the linkage assembly; the fourth tapered portion 461 is the same in shape and size as the second tapered portion 441, except that the fourth tapered portion 461 has a second through hole.

[0053] The outer diameter of the fourth connecting portion 453 is smaller than the outer diameter of the third connecting portion 452. Therefore, in certain specific scenarios, the outer wall of the third connecting portion 452 is in close contact with the inner wall of the mounting hole, and the outer wall of the fourth connecting portion 453 is in close contact with the inner wall of the second through hole. The fourth conical portion 461 is not connected to the conical channel 32. When the fourth connecting portion 453 is placed in the second through hole, the fourth conical portion 461 and the third conical portion 451 are coaxially arranged. Therefore, a fourth gap 462 is formed between the bottom of the fourth conical portion 461 and the conical channel 32. When the linkage assembly pushes the fourth When the conical portion 461 moves toward the side of the third conical portion 451, since the fourth conical portion 461 is eccentrically arranged with respect to the first channel 3, the top of the fourth conical portion 461 squeezes the top of the corresponding conical channel 32, and the conical channel 32 applies a reaction force to the fourth conical portion 461. The fourth conical portion 461 is connected to the fourth connecting portion 453, and the fourth connecting portion 453 is connected to the third connecting portion 452. The third connecting portion 452 is tightly attached to the inner wall of the mounting hole, so it contacts the second force-bearing portion 12, thereby generating a downward force on the second force-bearing portion 12.

[0054] In a preferred embodiment, the linkage component includes:

[0055] Two connecting structures are symmetrically arranged about the axis of the fourth tapered portion 461, each of which includes: a first connecting rod 463, a second connecting rod 464, and a third connecting rod 465, each of which is hinged at one end, and its hinge axis is a first hinge axis, the axis direction of the first hinge axis is a second direction, and the second direction is perpendicular to the first direction; the first connecting rod 463 is connected to the fourth tapered portion 461 away from the first hinge axis end; the third connecting rod 465 is hinged to the drill body 2 away from the first hinge axis end;

[0056] The linkage component also includes:

[0057] The abutment member 466 is hinged to the two second connecting rods 464 at the ends away from the first connecting rod 463 near the side of the fourth conical portion 461; and the fourth connecting portion 453 abuts against the abutment member 466 at the side of the second connecting rod 464.

[0058] Please refer to Figure 1-Figure 3As shown, two groups of the first connecting rods 463 and the second connecting rods 464 form a four-bar structure, the second direction is the direction perpendicular to the paper, the length of the fourth connecting portion 453 is long enough, and when the third conical portion 451 is threadedly connected to the conical channel 32, the fourth connecting portion 453 is abutted against the abutment 466 away from the end of the third conical portion 451; optionally, the first connecting rod 463 and the fourth conical portion 431 close to the abutment 466 can be threadedly connected by bolts, and the third connecting rod 465 is L-shaped, including a transverse portion and a vertical portion, the vertical portion is hinged to the first connecting rod 463 and the second connecting rod 464 away from the transverse portion end, and the transverse portion is hinged to the drill body 2 away from the vertical portion end, and the direction of its hinge axis is parallel to the direction of the first hinge axis.

[0059] When the third conical portion 451 rotates in the conical channel 32, causing the fourth connecting portion 453 to push the abutment 466 to the right, due to the action of the four-bar linkage, the two first connecting rods 463 form a leftward pushing force on the fourth conical portion 461, and when the fourth connecting portion 453 passes through the second through hole of the fourth conical portion 461, the fourth conical portion 461 and the third conical portion 451 are coaxially arranged, and both are eccentrically arranged with respect to the first channel 3, so the top of the first channel 3 forms a downward reaction force on the fourth conical portion 461, which acts on the second force-bearing portion 12 through the third connecting portion 452, generating downward pressure on the second force-bearing portion 12, thereby achieving balanced downward pressure on the blade 1 on both sides.

[0060] In addition, after the installation is completed, the third connecting rod 465 can be removed from the drill body 2 and the fourth tapered portion 461 can be taken out.

[0061] Example 3

[0062] On the basis of Example 1 or Example 2, further, the first connection portion 432 is threadedly connected to the inner wall of the main channel 31 , and the third connection portion 452 is threadedly connected to the inner wall of the main channel 31 .

[0063] like Figure 1-Figure 3As shown, the length of the first connecting portion 432 and the third connecting portion 452 along the first direction is greater than the length of the mounting hole, and the outer walls of the first connecting portion 432 and the third connecting portion 452 are provided with threads matching the inner walls of the main channel 31. When the first tapered portion 431 and the tapered channel 32 are threadedly connected, the first connecting portion 432 is threadedly connected to the main channel 31. When the third tapered portion 451 and the tapered channel 32 are threadedly connected, the third connecting portion 452 is threadedly connected to the main channel 31, thereby improving the locking force of the blade 1 and improving the stability of the drill bit.

[0064] The above description is merely a preferred embodiment of the present application and an illustration of the technical principles employed. Those skilled in the art should understand that the scope of the invention herein is not limited to the technical solutions formed by the specific combination of the above-mentioned technical features, but also encompasses other technical solutions formed by any combination of the above-mentioned technical features or their equivalents without departing from the inventive concept. For example, a technical solution formed by replacing the above-mentioned features with (but not limited to) technical features having similar functions disclosed in this application.

Claims

1. A drill bit, characterized in that: The drill bit comprises: A drill body (2), wherein a mounting end (21) of the drill body (2) is provided with a first passage (3) extending in a first direction, a mounting slot for inserting a blade (1) is arranged perpendicularly and passing through the first passage (3); the blade (1) has a mounting hole extending in the first direction; a locking mechanism (4) passing through the first passage (3) and the mounting hole locks the blade (1) on the drill body (2); The bottom of the inner wall of the mounting hole of the blade (1) and the parts arranged along the first direction are respectively a first force-bearing portion (11) and a second force-bearing portion (12); The locking mechanism (4) simultaneously applies a first force to the first force-bearing portion (11) and a second force to the second force-bearing portion (12) during the process of locking the blade (1) through the first passage (3) and the mounting hole; the first force and the second force are symmetrical about a center line of the blade (1) perpendicular to the first direction; The first channel (3) comprises a main channel (31) provided in the middle and tapered channels (32) provided symmetrically on both sides of the main channel (31) along the first direction, the axis of the first channel (3) being the first axis (33), the axis of the locking mechanism (4) being the second axis (41), and the first axis (33) being located on the side of the second axis (41) away from the mounting end (21); The locking mechanism (4) includes a first locking component (43) and a second locking component (44), wherein the first locking component (43) includes a first tapered portion (431) and a first connecting portion (432) distributed along the first direction; the second locking component (444) includes a second tapered portion (441) and a second connecting portion (442) distributed along the first direction; the first connecting portion (432) has a first space (433) therein, the first connecting portion (432) passes through the mounting hole, and the second connecting portion (442) is placed in the first space (433) and connected to the first connecting portion (432); the first tapered portion (431) is threadedly connected to the inner wall of the tapered channel (32) near the mounting end (21), and the second tapered portion (441) is threadedly connected to the inner wall of the other tapered channel (32) near the mounting end (21).

2. The drill bit according to claim 1, characterized in that: The inner wall of the first connecting portion (432) is provided with an internal thread, and the outer wall of the second connecting portion (442) is provided with an external thread matching the internal thread.

3. The drill bit according to claim 1, wherein: Along the first direction, the length of the first connecting portion (432) is greater than or equal to the length of the mounting hole.

4. The drill bit according to any one of claims 1 to 3, wherein: The edge of the mounting hole away from the mounting end (21) is placed in the first channel (3).

5. The drill bit according to any one of claims 1 to 3, characterized in that: The first connecting portion (432) is threadedly connected to the inner wall of the main body channel (31).

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