A drill bit
The drill bit connection method with staggered screw holes and inclined surface design solves the stress concentration problem caused by bolt side tightening connection, realizes stable clamping and force balance of the cutting tool, and improves machining stability and accuracy.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- DONGGUAN CHUANSHANJIA PRECISION TOOL CO LTD
- Filing Date
- 2025-05-30
- Publication Date
- 2026-06-12
AI Technical Summary
Existing drill bits with bolted side-tightening connections are prone to stress concentration during drilling, which can lead to sudden breakage of the drill bit, drill body, and workpiece, resulting in serious consequences.
A stable connection between the drill rod and the cutting tool is achieved by using the first and second screw holes that are staggered, and by matching the inclined surface of the screw rod with the hole position, combined with the shaft hole and the positioning post, to achieve stable clamping and force balance of the cutting tool.
It effectively prevents blade runout and eccentricity, ensures uniform cutting, improves machining stability and accuracy, reduces vibration, and extends tool life.
Smart Images
Figure CN224346998U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of cutting technology, and more specifically to a drill bit. Background Technology
[0002] In metal hole machining processes, the use of disposable drill bits with replaceable cutting heads can significantly reduce production costs and improve economic efficiency.
[0003] Currently, the most commonly used connection method is the bolt side tightening type. This type of connection will create a stress concentration area, which may cause sudden breakage during drilling, resulting in the serious consequence of the tool head, tool body and workpiece being scrapped at the same time.
[0004] Therefore, we propose a drill bit that provides a stable connection between the drill rod and the cutting tool. Utility Model Content
[0005] In view of this, the present invention provides a drill bit.
[0006] To achieve the above objectives, this utility model adopts the following technical solution: a drill bit, comprising: a drill rod and a cutting blade, wherein the front end of the drill rod forms a cutting blade position, the cutting blade is assembled in the cutting blade position, the drill rod is provided with a first threaded hole; the cutting blade is provided with a second threaded hole, a screw rod passes through the first threaded hole and the second threaded hole to lock the cutting blade in the cutting blade position; the first threaded hole has a first central axis, and the second threaded hole has a second central axis; the first central axis and the second central axis are offset and do not overlap;
[0007] The screw rod has a head with a second inclined surface at a 45° angle; the drill rod has a first hole position, which is coaxially distributed with the first screw hole and is connected to the first screw hole. The first hole position has a first inclined surface at a 45° angle, and the first inclined surface and the second inclined surface match each other.
[0008] As a preferred embodiment of this utility model, a shaft hole is provided along the axial direction of the drill rod, the shaft hole is connected to the cutting tool position, the cutting tool is provided with a positioning post, the inner bottom wall of the cutting tool position forms a first support surface, and the bottom of the cutting tool forms a second support surface; when the cutting tool is assembled in the cutting tool position, the positioning post is inserted into the shaft hole, and the first support surface and the second support surface abut against each other.
[0009] In a preferred embodiment of this invention, the first central axis passes through the blade position.
[0010] As a preferred embodiment of this utility model, the blade has a first side surface, a second side surface, a third side surface, a fourth side surface, an end face, and a second supporting surface; the second screw hole penetrates the third side surface and the fourth side surface; the end face and the second supporting surface are opposite to each other.
[0011] As a preferred embodiment of this utility model, the first side and the second side are opposite to each other, and the first side and the second side are provided with the outer edge of the blade.
[0012] As a preferred embodiment of this utility model, the outer edge of the blade is inclined.
[0013] As a preferred embodiment of this utility model, the end face of the blade is provided with a vertex at the center, and a cutting surface is provided outward from the vertex, with the cutting surface being set at 130°.
[0014] As a preferred embodiment of this utility model, the end face of the blade is provided with a main cutting surface, one main cutting surface connects a cutting surface and a third side surface, and one main cutting surface connects a cutting surface and a fourth side surface; the end face of the blade is provided with a flank face, the flank face connects the cutting surface and the main cutting surface.
[0015] In a preferred embodiment of this invention, the main cutting surface is set at 150°.
[0016] As can be seen from the above technical solution, compared with the prior art, this utility model has the following beneficial technical effects:
[0017] In this invention, the central axis of the first screw hole is lower than the central axis of the second screw hole. During the tightening of the screw rod 300 in hole section A, the screw rod applies downward pressure to the blade. After the screw rod passes through the first screw hole and the second screw hole and is tightened, the screw rod forms a locking force and a downward pressure on the blade. The locking force can clamp the blade in the blade position, and the downward pressure can press the blade down in the blade position, effectively preventing the blade from jumping upward.
[0018] This utility model has a shaft hole at the blade position and a positioning pin on the blade. After assembly, the positioning pin is inserted into the shaft hole to effectively fix the blade and prevent the blade from being eccentric.
[0019] This invention provides a second support surface at the bottom of the blade and a first support surface at the blade position. After assembly, the first and second support surfaces abut against each other to ensure that the blade is subjected to balanced forces and that the cutting is uniform.
[0020] The remaining beneficial technical effects of this utility model are embodied in the specific embodiments. Attached Figure Description
[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.
[0022] Figure 1 This is a schematic diagram of the drill bit of this utility model;
[0023] Figure 2 This is a partial exploded view of the drill bit of this utility model;
[0024] Figure 3 This is a cross-sectional schematic diagram of the drill bit of this utility model;
[0025] Figure 4 To be Figure 3 A diagram showing the result after the middle screw rod has been removed;
[0026] Figure 5 for Figure 4 Enlarged view of point A in the middle;
[0027] Figure 6 This is a schematic diagram of the blade in this utility model;
[0028] Figure 7 This is a side angle diagram of the blade in this utility model;
[0029] Figure 8 This is a top view of the blade in this utility model;
[0030] Figure 9 This is a frontal view of the blade in this utility model.
[0031] Explanation of reference numerals in the attached figures
[0032] Drill rod 100; cutting tool position 101; shaft hole 102; first support surface 103; first screw hole 110; first central axis 111; first hole position 120; first inclined surface 121; left side 130; hole section A 131; right side 140; hole section B 141; internal cooling hole 150; cutting tool 200; first side 2001; second side 2002; third side 2003; fourth side 2004; end face 2005; positioning post 202; second support surface 203; cutting tool outer edge 204; cutting surface 205; main cutting surface 206; flank face 207; second screw hole 210; second central axis 211; screw rod 300; head 310; second inclined surface 311. Detailed Implementation
[0033] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.
[0034] In the description of this application, it should be understood that the terms "longitudinal," "radial," "length," "width," "thickness," "upper," "lower," "left," "right," "front," "rear," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. In the description of this application, unless otherwise stated, "a plurality of" means two or more.
[0035] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0036] Please see Figure 1-9 As shown, a drill bit includes: a drill rod 100 and a cutting blade 200. The drill rod 100 has a cutting blade position 101 at its front end, and the cutting blade 200 is fitted into the cutting blade position 101. The drill rod 100 has a first threaded hole 110; the cutting blade 200 has a second threaded hole 210. A screw rod 300 passes through the first threaded hole 110 and the second threaded hole 210 to lock the cutting blade 200 into the cutting blade position 101. The first threaded hole 110 has a first central axis 111, and the second threaded hole 210 has a second central axis 211. The first central axis 111 and the second central axis 211 are offset and do not overlap.
[0037] The drill rod 100 is a long rod made of high-hardness metal material, and its length direction is axial; for example Figure 1 The upper end of the drill rod 100 shown is the front end, and the lower end is the rear end. The cutting tool position 101 extends from the front end of the drill rod 100 towards the rear end. Figure 2 and Figure 4 As shown, after the drill rod 100 is provided with the blade position 101, the front end of the drill rod 100 is divided into a left side part 130 and a right side part 140 through the blade position 101. The first threaded hole 110 is opened through both the left side part 130 and the right side part 140. A hole segment A131 is formed in the left side part 130, and a hole segment B141 is formed in the right side part 140. Hole segment A131 and hole segment B141 form the first threaded hole 110. Hole segment A131 is provided with internal thread, while hole segment B141 is not provided with internal thread.
[0038] like Figure 5 As shown, the first central axis 111 is positioned lower than the second central axis 211, specifically, the first central axis 111 is 0.1-0.2 mm lower than the second central axis 211;
[0039] Optionally, the first central axis 111 is 0.1 mm lower than the second central axis 211;
[0040] Optionally, the first central axis 111 is 0.2 mm lower than the second central axis 211;
[0041] Optionally, the first central axis 111 is 0.15 mm lower than the second central axis 211.
[0042] like Figure 5 As shown, after the blade 200 is installed in the blade position 101, during the installation of the screw rod 300 from right to left, the screw rod 300 passes through the hole section B141 and the second screw hole 210. The screw rod 300 is tightened with a wrench. Since the position of the hole section B141 is lower than the second screw hole 210, the screw rod 300 applies downward pressure to the blade 200 during the tightening of the screw rod in the hole section A131.
[0043] After the screw rod 300 passes through the first screw hole 110 and the second screw hole 120 and is tightened, the screw rod 300 forms a locking force and a downward pressure on the blade 200. The locking force can clamp the blade 200 in the blade position 101, and the downward pressure can press the blade 200 down in the blade position 101, effectively preventing the blade 200 from jumping upward.
[0044] Furthermore, the screw rod 300 has a head 310, and the head 310 is provided with a second inclined surface 311 at a 45° angle; the drill rod 100 is provided with a first hole 120, the first hole 120 and the first screw hole 110 are coaxially distributed and connected, the first hole 120 is provided with a first inclined surface 121 at a 45° angle, and the first inclined surface 121 and the second inclined surface 311 match; specifically, the first inclined surface 121 and the second inclined surface 311 are in contact.
[0045] In one embodiment, a shaft hole 102 is provided along the axial direction of the drill rod 100, the shaft hole 102 communicates with the cutting tool position 101, the cutting tool 200 is provided with a positioning post 202, the inner bottom wall of the cutting tool position 101 forms a first support surface 103, and the bottom of the cutting tool 200 forms a second support surface 203; when the cutting tool 200 is assembled in the cutting tool position 101, the positioning post 202 is inserted into the shaft hole 102, and the first support surface 103 and the second support surface 203 abut against each other.
[0046] like Figure 2As shown, the shaft hole 102 is cylindrical, and the positioning post 202 is also cylindrical. The shaft hole 102 and the positioning post 202 play a positioning role, fixing the blade 200 so that the blade 200 will not be eccentric.
[0047] Furthermore, the axis of the positioning post 202 serves as the central axis of the blade 200.
[0048] Continue as Figure 2 As shown, both the first support surface 103 and the second support surface 203 are planar structures, which ensures that the blade 200 is subjected to balanced forces and uniform cutting.
[0049] The positioning post 202 protrudes downward from the second support surface 203, so that the positioning post 202 can be inserted into the shaft hole 102.
[0050] In one embodiment, the blade 200 has a first side surface 2001, a second side surface 2002, a third side surface 2003, a fourth side surface 2004, an end face 2005, and a second support surface 203; the second screw hole 210 penetrates the third side surface 2003 and the fourth side surface 2004; the end face 2005 and the second support surface 203 are opposite to each other;
[0051] Specifically, the blade 200 is also made of a high-hardness metal material, with the first side 2001 and the second side 2002 facing away from each other, as shown below. Figure 6 As shown, the first side 2001 and the second side 2002 are provided with an outer blade 204, which is inclined; as Figure 7 As shown, the outer cutting edge 204 of the insert on the first side 2001 is inclined from the upper right to the lower left. The outer cutting edge 204 plays a guiding and stabilizing role. During the drilling process, the outer cutting edge 204 is close to the hole wall, which plays a guiding role, prevents deviation or swing, and ensures the straightness and positional accuracy of the hole. It also reduces vibration. The well-designed outer cutting edge 204 can disperse the cutting force, reduce vibration, and improve the machining stability, which is especially important in deep hole machining.
[0052] In one embodiment, the end face 2005 of the blade 200 has a vertex at its center, and the central axis of the blade 200 passes through the vertex; a cutting surface 205 is provided outward from the vertex, and the cutting surface 205 is set at 130°; for example Figure 8 As shown, the central axis of the positioning post 202 is set perpendicular to the paper surface, and the blades 200 are symmetrically arranged around the central axis.
[0053] like Figure 8 As shown, when rotating, the blade 200 rotates counterclockwise, as... Figure 9 As shown, the vertex is the highest point of the blade 200, and the cutting surface 205 extends from the vertex to both sides as follows: Figure 9 As shown, the workpiece is inclined downwards during drilling. Figure 9 Above the 200mm caliper blade, the drill bit is like... Figure 9 As shown, when drilling from bottom to top, the cutting surface 205 is the part of the drill bit that first contacts the workpiece. It is responsible for cutting into the material surface and forming the initial cutting force. Its sharpness and geometry directly affect the cutting efficiency and resistance.
[0054] In one embodiment, the end face 2005 of the insert 200 is provided with a main cutting surface 206, one main cutting surface 206 connects a cutting surface 205 and a third side surface 2003, and one main cutting surface 206 connects a cutting surface 205 and a fourth side surface 2004; the end face 2005 of the insert 200 is provided with a flank face 207, the flank face 207 connects the cutting surface 205 and the main cutting surface 206; the main cutting surface 206 is set at 150°.
[0055] Specifically, there are two main cutting surfaces 206. One main cutting surface 206 connects a cutting surface 205 and a third side surface 2003, and the other main cutting surface 206 connects a cutting surface 205 and a fourth side surface 2004. The main cutting surface 206, as part of the main cutting edge, undertakes the main material removal task, cutting the material and forming chips through rotation and feed motion.
[0056] More specifically, the rake face 207 is inclined downwards and backwards from the cutting edge, forming an angle with the workpiece surface; the insert 200 has a rake angle, which can reduce cutting force. A larger positive rake angle can make the chips flow more smoothly across the rake face, reducing cutting force and energy consumption.
[0057] In one embodiment, the drill rod 100 is provided with an internal cooling hole 150, which extends through the upper end of the drill rod 100 and can spray out coolant to achieve a cooling effect.
[0058] The drill bit of this invention can be mounted on a power unit, and driven by the power unit to rotate at high speed to achieve the hole-opening function.
[0059] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
[0060] Furthermore, the technical solutions of the various embodiments of this utility model can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the protection scope claimed by this utility model.
Claims
1. A drill bit, comprising: A drill rod (100) and a cutting tool (200), wherein the front end of the drill rod (100) has a cutting tool position (101), and the cutting tool (200) is mounted in the cutting tool position (101), characterized in that: The drill rod (100) is provided with a first screw hole (110); the cutting blade (200) is provided with a second screw hole (210), and the screw rod (300) passes through the first screw hole (110) and the second screw hole (210) to lock the cutting blade (200) in the cutting blade position (101); the first screw hole (110) has a first central axis (111), and the second screw hole (210) has a second central axis (211); the first central axis (111) and the second central axis (211) are offset and do not overlap; The screw rod (300) has a head (310) with a second inclined surface (311) at a 45° angle. The drill rod (100) has a first hole (120) with the first screw hole (110) coaxially distributed and connected to the first screw hole (110). The first hole (120) has a first inclined surface (121) at a 45° angle, and the first inclined surface (121) matches the second inclined surface (311).
2. A drill bit according to claim 1, characterized in that: A shaft hole (102) is provided along the axial direction of the drill rod (100), the shaft hole (102) is connected to the cutting tool position (101), the cutting tool (200) is provided with a positioning post (202), the inner bottom wall of the cutting tool position (101) forms a first support surface (103), and the bottom of the cutting tool (200) forms a second support surface (203); when the cutting tool (200) is assembled in the cutting tool position (101), the positioning post (202) is inserted into the shaft hole (102), and the first support surface (103) and the second support surface (203) abut against each other.
3. A drill bit according to claim 2, characterized in that: The first central axis (111) passes through the blade position (101).
4. A drill bit according to any one of claims 2-3, characterized in that: The blade (200) has a first side (2001), a second side (2002), a third side (2003), a fourth side (2004), an end face (2005), and a second support surface (203); the second screw hole (210) passes through the third side (2003) and the fourth side (2004); the end face (2005) and the second support surface (203) are opposite to each other.
5. A drill bit according to claim 4, characterized in that: The first side (2001) and the second side (2002) are opposite to each other, and the first side (2001) and the second side (2002) are provided with the outer edge (204) of the blade.
6. A drill bit according to claim 5, characterized in that: The outer edge (204) of the blade is set at an angle.
7. A drill bit according to claim 1, characterized in that: The blade (200) has a vertex at the center of its end face (2005), and a cutting surface (205) is provided outward from the vertex, with the cutting surface (205) set at 130°.
8. A drill bit according to claim 7, characterized in that: The end face (2005) of the blade (200) is provided with a main cutting surface (206), one main cutting surface (206) connects a cutting surface (205) and a third side surface (2003), and one main cutting surface (206) connects a cutting surface (205) and a fourth side surface (2004); the end face (2005) of the blade (200) is provided with a flank face (207), and the flank face (207) connects the cutting surface (205) and the main cutting surface (206).
9. A drill bit according to claim 8, characterized in that: The main cutting surface (206) is set at 150°.