High-efficiency self-lubricating twist drill

Abstract

This application relates to a high-efficiency self-lubricating twist drill bit, specifically within the technical field of twist drill bits, and includes a drill bit body. This application utilizes a microtexture and helical guide grooves. The microtexture creates an oil storage space in the cutting edge region. During cutting operations, the lubricating oil stored within the microtexture is slowly released under frictional heat and pressure, improving the lubrication between the cutting edge region and the hole wall, effectively reducing contact resistance. The helical guide grooves quickly guide chips generated during cutting to the chip removal grooves, improving chip removal efficiency, preventing chip accumulation in the hole, and reducing additional tool wear. Simultaneously, the double-strip design of the annular cutting edge, while maintaining guiding stability, combined with the flow-guiding effect of the helical guide grooves, accelerates airflow in the cutting area, enhancing the heat dissipation performance of the annular cutting edge. This achieves a highly efficient and durable self-lubricating effect for the twist drill bit in deep hole machining.

Description

Technical Field

[0001] This application relates to twist drills, and more particularly to a high-efficiency self-lubricating twist drill. Background Technology

[0002] As modern manufacturing moves towards higher strength and precision, traditional twist drills commonly suffer from problems such as high cutting temperatures, poor chip removal, and rapid edge wear when machining high-hardness materials. Currently, the industry mainly improves performance by optimizing drill tip geometry, using coating technology, or high-pressure cooling, but due to material properties, it remains difficult to significantly improve tool life and machining efficiency.

[0003] A current patent (publication number: CN103722220A) discloses a twist drill bit with an annular cutting edge, comprising a head, a neck, and a shank located on a coaxial cylinder. The diameter of the head is d1, the diameter of the neck is d2, and the diameter of the shank is d3. The head and neck are provided with helical grooves and a cutting back forming the solid portion of the grooves. A main cutting edge is provided on the end face of the grooves. A cutting edge of length d1 is provided along the axial direction of the head, and a first annular cutting edge is provided on the cutting back at the axial length d1 of the head. The shank is clamped on a transmission machine tool. Therefore, the drill bit of the present invention is manufactured using a single piece of cemented carbide material. Furthermore, by providing the first and second annular cutting edges, it can both guide the drill bit and improve its stability during drilling, as well as reduce friction between the drill bit and the hole wall.

[0004] While the device described in the aforementioned comparative document solves the problem of friction between the drill bit and the hole wall, its insufficient chip removal efficiency during deep hole machining easily leads to chip accumulation inside the hole. This not only increases additional tool wear but also reduces the heat dissipation performance of the cutting edge due to frictional heat accumulation. Furthermore, the surface lubrication performance of the annular cutting edge structure gradually decreases during prolonged high-speed cutting, failing to continuously and effectively reduce contact resistance with the hole wall. To address these issues, a high-efficiency self-lubricating twist drill bit is proposed. Utility Model Content

[0005] The purpose of this application is to provide a high-efficiency self-lubricating twist drill bit, which has the advantages of high efficiency and self-lubrication, and solves the problems of low chip removal efficiency, insufficient heat dissipation performance of the cutting edge, and increased contact resistance caused by the decline of the surface lubrication performance of the annular cutting edge over time in the deep hole machining of existing twist drill bits.

[0006] The present application provides a high-efficiency self-lubricating twist drill bit with the following technical solution: it includes a drill bit body, which is composed of a head, a neck and a shank that are fixedly connected in sequence; The head is provided with a main cutting edge at one end, and an annular cutting edge is provided on the surface of the head. There are two annular cutting edge bands. A chip removal groove is provided inside the head. A back area is provided on the back of the main cutting edge. Multiple micro-textures are provided inside the back area. A spiral guide groove is provided in the transition area between the back area and the chip removal groove. By adopting the above technical solution, and by setting microtexture and spiral guide groove, an oil storage space can be formed in the back of the tool under the action of microtexture. When the drill bit is cutting, the lubricating oil stored in the microtexture will be slowly released under the action of frictional heat and pressure, which can improve the lubrication state between the back of the tool and the hole wall, and effectively reduce contact resistance. Under the action of spiral guide groove, the chips generated during the cutting process can be quickly guided to the chip removal groove, which can improve chip removal efficiency, avoid chip accumulation in the hole, and reduce additional tool wear. At the same time, the double-strip design of the annular cutting edge, while maintaining guiding stability, can accelerate the air flow in the cutting area in conjunction with the flow-guiding effect of the spiral guide groove, and enhance the heat dissipation performance of the annular cutting edge, thereby achieving a high-efficiency self-lubricating effect and durability of twist drill bit in deep hole machining.

[0007] Preferably, the microtexture is a fish-scale-like micro-pit, and is arranged in an alternating pattern along the length of the blade back region; By adopting the above technical solution and setting a micro-texture structure with fish-scale-like micro-pits, the uneven surface shape can significantly increase the lubricant adsorption capacity. The staggered arrangement can ensure the uniform distribution of lubricant in the blade back area and avoid local lubrication deficiency.

[0008] Preferably, the microtexture is filled with a lubricant; By adopting the above technical solution, and by filling the microtexture with lubricant, an initial lubrication layer can be formed before the drill bit begins cutting. When the twist drill bit performs deep hole machining, as the friction between the back of the drill bit and the hole wall intensifies, the lubricant in the microtexture will gradually seep out under the action of the heat and pressure generated by the friction, continuously lubricating and replenishing the contact surface. This active release lubrication method can avoid the problem that the lubricant is difficult to continuously reach the deep hole machining area in traditional lubrication methods, and can ensure the continuity and stability of the lubrication effect throughout the cutting process.

[0009] Preferably, the microtextures are distributed in a gradient along the head, with a high density near the head and a low density near the shank. By adopting the above technical solution, and by setting the microtexture to be distributed in a gradient along the head axis, the high-density microtexture near the head area can quickly provide sufficient lubrication support in the initial stage of cutting, which can meet the lubrication needs of the intense friction when the head and the hole wall just come into contact. The low-density microtexture near the shank area can rationally allocate the amount of lubricant storage according to the decrease of friction intensity, which can avoid unnecessary lubricant waste. Through the differential distribution of density, the precise and efficient utilization of lubricant can be achieved.

[0010] Preferably, the cross-section of the spiral guide channel is U-shaped; By adopting the above technical solution and setting the cross-section of the spiral guide channel to U-shape, the flow efficiency of the cutting fluid in the channel can be improved. Compared with the traditional V-shaped or rectangular channel, the U-shaped structure has a larger volume and a smoother inner wall transition, which can reduce the resistance loss during the flow of cutting fluid. It can enable the cutting fluid to be delivered from the drill bit shank to the cutting area of ​​the head more quickly. At the same time, the rounded bottom design of the U-shaped channel can prevent cutting chips from accumulating in the channel, reduce the risk of lubrication interruption caused by chip blockage, and ensure that the delivery channel of cutting fluid and lubricant is always unobstructed.

[0011] Preferably, there are two spiral guide grooves, and the spiral guide grooves and the chip removal grooves are connected by a spiral transition. By adopting the above technical solution, and by using the spiral transition joint of the spiral guide groove and the chip removal groove, the cutting fluid can form a continuous spiral flow path during the process of entering the chip removal groove from the guide groove. This flow path is consistent with the rotation direction of the drill bit, and the centrifugal force generated by the rotation of the drill bit can be used to further accelerate the delivery speed of the cutting fluid.

[0012] Preferably, the annular blade is a composite heat dissipation structure consisting of a copper alloy substrate and a hard alloy surface layer; By adopting the above technical solution, and by setting a copper alloy substrate and a cemented carbide surface layer, the copper alloy substrate can quickly conduct the heat generated during the cutting process from the surface of the cutting edge to the inside of the drill bit, and can carry away the heat of the cutting fluid, thereby reducing the working temperature of the cutting edge area. The cemented carbide surface layer can improve the wear resistance and impact resistance of the cutting edge, and can avoid the deformation or accelerated wear of the cutting edge caused by high temperature softening.

[0013] Preferably, the surface of the cemented carbide layer is covered with a TiAlN nano-multilayer coating; By adopting the above technical solution and setting a TiAlN nano-multilayer coating, the surface properties of the cemented carbide surface can be improved. The TiAlN nano-multilayer coating has high hardness and excellent oxidation resistance, which can reduce the direct friction between the cutting edge and the workpiece material during the cutting process, reduce the coefficient of friction, and reduce the generation of cutting heat.

[0014] In summary, this application includes at least one of the following beneficial technical effects: 1. This high-efficiency self-lubricating twist drill bit, through the setting of micro-texture and spiral guide groove, can form an oil storage space in the back area under the action of micro-texture. When the drill bit is cutting, the lubricating oil stored in the micro-texture will be slowly released under the action of frictional heat and pressure, which can improve the lubrication state between the back area and the hole wall, effectively reducing contact resistance. Under the action of spiral guide groove, the chips generated during the cutting process can be quickly guided to the chip removal groove, which can improve chip removal efficiency, avoid chip accumulation in the hole, and reduce additional tool wear. At the same time, the double-strip design of the annular cutting edge, while maintaining the guiding stability, can accelerate the air flow in the cutting area in conjunction with the guiding effect of the spiral guide groove, and enhance the heat dissipation performance of the annular cutting edge, thereby achieving a high-efficiency self-lubricating effect and durability of the twist drill bit in deep hole machining; 2. This high-efficiency self-lubricating twist drill bit utilizes a micro-textured structure with fish-scale-like micro-pits. The uneven surface significantly increases the lubricant's adsorption capacity. The staggered arrangement ensures uniform lubricant distribution across the cutting edge area, preventing localized lubrication deficiencies. By filling the micro-texture with lubricant, an initial lubrication layer is formed before the drill begins cutting. During deep hole drilling, as friction between the cutting edge and the hole wall intensifies, the lubricant within the micro-texture gradually seeps out under the heat and pressure generated by friction, continuously replenishing lubrication to the contact surface. This active release... This lubrication method avoids the problem of lubricant not being able to continuously reach the deep hole machining area in traditional lubrication methods. It can ensure the continuity and stability of the lubrication effect throughout the cutting process. By setting microtextures in a gradient distribution along the head axis, the high-density microtextures near the head area can quickly provide sufficient lubrication support in the initial stage of cutting, which can meet the lubrication needs of the intense friction when the head just comes into contact with the hole wall. The low-density microtextures near the shank area can rationally allocate the amount of lubricant storage according to the decrease of friction intensity, which can avoid unnecessary lubricant waste. Through the differential distribution of density, the precise and efficient use of lubricant can be achieved. Attached Figure Description

[0015] Figure 1 This is a frontal three-dimensional structural diagram of this application; Figure 2 This is a schematic diagram of the through groove in this application; Figure 3 This is a schematic diagram of the main cutting edge in this application; Figure 4 This is a schematic diagram of the annular cutting edge in this application; Figure 5 This is a schematic diagram of the microtexture structure in this application.

[0016] In the figure: 1. Drill body; 11. Head; 12. Neck; 13. Shank; 14. Spiral guide groove; 15. Annular cutting edge; 1501. Copper alloy substrate; 1502. Carbide surface layer; 1503. TiAlN nano multilayer coating; 16. Back of the tool area; 1601. Microtexture; 17. Chip removal groove; 18. Main cutting edge. Detailed Implementation

[0017] The following is in conjunction with the appendix Figure 1 - Appendix Figure 5 This application will be described in further detail below.

[0018] Example 1: A high-efficiency self-lubricating twist drill bit, referring to... Figure 1 , Figure 2 , Figure 4 and Figure 5 It includes a drill bit body 1, which is composed of a head 11, a neck 12 and a shank 13 that are fixedly connected in sequence. The head 11 has a main cutting edge 18 at one end, and two annular cutting edges 15 on its surface. A chip removal groove 17 is located inside the head 11. A backing region 16 is located on the back of the main cutting edge 18, and multiple microtextures 1601 are arranged inside the backing region 16. A spiral guide groove 14 is provided in the transition area between the backing region 16 and the chip removal groove 17. By providing the microtextures 1601 and the spiral guide groove 14, an oil storage space can be formed in the backing region 16 under the action of the microtextures 1601. When the drill bit performs cutting operations, the lubricating oil stored in the microtextures 1601 will be released during frictional heat. The slow release under pressure can improve the lubrication between the back of the tool 16 and the hole wall, effectively reducing contact resistance. Under the action of the spiral guide groove 14, the chips generated during the cutting process can be quickly guided to the chip removal groove 17, which can improve chip removal efficiency, prevent chips from accumulating in the hole, and reduce additional tool wear. At the same time, the double-strip design of the annular cutting edge 15, while maintaining guiding stability, can accelerate the airflow in the cutting area in conjunction with the flow-guiding effect of the spiral guide groove 14, and enhance the heat dissipation performance of the annular cutting edge 15. Thus, the twist drill bit can achieve a high-efficiency self-lubricating effect and durability in deep hole machining.

[0019] Please see Figure 1 and Figure 5The microtexture 1601 consists of fish-scale-like micro-pits arranged in an alternating pattern along the length of the cutting edge region 16. This fish-scale-like micro-pit structure significantly increases the lubricant's adsorption capacity due to its surface irregularities. The alternating arrangement ensures uniform lubricant distribution in the cutting edge region 16, preventing localized lubrication deficiencies. The microtexture 1601 is filled with lubricant, forming an initial lubrication layer before the drill begins cutting. During deep hole drilling, as friction between the cutting edge region 16 and the hole wall intensifies, the lubricant within the microtexture 1601 gradually seeps out under the heat and pressure generated by friction, continuously replenishing lubrication to the contact surface. This active lubrication method avoids the drawbacks of traditional lubrication methods. To address the problem of lubricant difficulty in continuously reaching the deep hole machining area, this method ensures the continuity and stability of lubrication throughout the cutting process. The microtexture 1601 is axially gradient distributed on the head 11, with a high density near the head 11 and a low density near the shank 13. By setting the microtexture 1601 to be axially gradient distributed on the head 11, the high-density microtexture 1601 near the head 11 can quickly provide sufficient lubrication support in the initial stage of cutting, meeting the lubrication needs of intense friction when the head 11 first contacts the hole wall. The low-density microtexture 1601 near the shank 13 can rationally allocate the amount of lubricant stored according to the decrease in friction intensity, avoiding unnecessary lubricant waste. Through the differential density distribution, precise and efficient utilization of lubricant can be achieved.

[0020] Please see Figure 1 The spiral guide channel 14 has a U-shaped cross-section. By setting the cross-section of the spiral guide channel 14 to U-shape, the flow efficiency of the cutting fluid in the channel can be improved. Compared with the traditional V-shaped or rectangular channel, the U-shaped structure has a larger volume and a smoother inner wall transition, which can reduce the resistance loss during the flow of cutting fluid. It can enable the cutting fluid to be delivered from the drill shank 13 to the cutting area of ​​the head 11 more quickly. At the same time, the bottom arc design of the U-shaped channel can prevent cutting chips from accumulating in the channel, reduce the risk of lubrication interruption caused by chip blockage, and ensure that the delivery channel of cutting fluid and lubricant is always unobstructed. There are two spiral guide channels 14. The spiral guide channel 14 and the chip removal channel 17 are connected by a spiral transition. By using the spiral transition connection between the spiral guide channel 14 and the chip removal channel 17, the cutting fluid can form a continuous spiral flow path in the process of entering the chip removal channel 17 from the guide channel. This flow path is consistent with the rotation direction of the drill bit, and the centrifugal force generated by the rotation of the drill bit can be used to further accelerate the delivery speed of the cutting fluid.

[0021] Please see Figure 4The annular cutting edge 15 is a composite heat dissipation structure consisting of a copper alloy substrate 1501 and a cemented carbide surface layer 1502. By combining the copper alloy substrate 1501 and the cemented carbide surface layer 1502, the copper alloy substrate 1501 can quickly conduct heat generated during cutting from the cutting edge surface to the drill bit's interior, carrying away heat from the cutting fluid and reducing the operating temperature of the cutting edge area. The cemented carbide surface layer 1502 enhances the wear resistance and impact resistance of the cutting edge, preventing deformation or accelerated wear due to high-temperature softening. The surface of the cemented carbide surface layer 1502 is covered with a TiAlN nano-multilayer coating 1503. This TiAlN nano-multilayer coating 1503 improves the surface properties of the cemented carbide surface layer 1502. The TiAlN nano-multilayer coating 1503 possesses high hardness and excellent oxidation resistance, reducing direct friction between the cutting edge and the workpiece material during cutting, lowering the coefficient of friction, and reducing the generation of cutting heat.

[0022] The implementation principle of this application embodiment is as follows: when the twist drill bit performs cutting operations, the main cutting edge 18 of the head 11 first contacts the workpiece, and the material is cut by the high-speed rotation of the main cutting edge 18. During this process, the lubricant stored in the microtexture 1601 of the back of the cutter 16 can be slowly released under the action of frictional heat and pressure, forming a continuous lubricating film between the back of the cutter 16 and the hole wall, effectively reducing contact resistance. Among them, the two spiral guide grooves 14 can quickly guide the cutting fluid and part of the lubricant to the chip removal groove 17 under the centrifugal force generated by the rotation of the drill bit. After mixing with the chips generated by cutting, the chips are discharged out of the hole in time by means of the spiral structure of the chip removal groove 17, thus avoiding chip accumulation. Among them, the copper alloy substrate 1501 of the annular cutting edge 15 can quickly conduct cutting heat, which is carried away by the cutting fluid. The TiAlN nano multilayer coating 1503 of the cemented carbide surface layer 1502 can reduce direct friction with the workpiece and reduce the coefficient of friction, which can further reduce the generation of cutting heat. Through the synergistic effect of each structure, the drill bit can achieve efficient self-lubrication and long-term stable operation in deep hole machining.

Claims

1. A high-efficiency self-lubricating twist drill bit, comprising a drill bit body (1), characterized in that: The drill bit body (1) is composed of a head (11), a neck (12) and a shank (13) that are fixedly connected in sequence; One end of the head (11) is provided with a main cutting edge (18), and the surface of the head (11) is provided with an annular cutting edge (15). There are two annular cutting edge (15). The head (11) is provided with a chip removal groove (17). The back of the main cutting edge (18) is provided with a back area (16). The back area (16) is provided with multiple micro-textures (1601). The transition area between the back area (16) and the chip removal groove (17) is provided with a spiral guide groove (14).

2. The high-efficiency self-lubricating twist drill bit according to claim 1, characterized in that: The microtexture (1601) consists of fish-scale-like micro-pits, which are arranged in an alternating pattern along the length of the blade back region (16).

3. The high-efficiency self-lubricating twist drill bit according to claim 1, characterized in that: The microtexture (1601) is filled with a lubricant.

4. The high-efficiency self-lubricating twist drill bit according to claim 1, characterized in that: The microtexture (1601) is axially gradient distributed on the head (11), with a high density of microtexture (1601) near the head (11) and a low density of microtexture (1601) near the shank (13).

5. The high-efficiency self-lubricating twist drill bit according to claim 1, characterized in that: The cross-section of the spiral guide groove (14) is U-shaped.

6. The high-efficiency self-lubricating twist drill bit according to claim 1, characterized in that: The number of spiral guide grooves (14) is two, and the spiral guide grooves (14) and the chip removal grooves (17) are connected by a spiral transition.

7. The high-efficiency self-lubricating twist drill bit according to claim 1, characterized in that: The annular blade (15) is a composite heat dissipation structure consisting of a copper alloy substrate (1501) and a hard alloy surface layer (1502).

8. The high-efficiency self-lubricating twist drill bit according to claim 7, characterized in that: The surface of the cemented carbide layer (1502) is covered with a TiAlN nano-multilayer coating (1503).

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