PCB drill bit with high chip removal

Abstract

The application discloses a high-chip-removal PCB drill, and relates to the technical field of drills.The drill body main body is provided with a drill tip part and a drill body part at the end of the drill body main body; a first chip removal groove spirally extending around the axial direction of the drill body main body is formed on the drill body main body; the first chip removal groove extends from the drill tip part to the drill body part; a second chip removal groove spirally extending around the axial direction of the drill body main body is formed in the first chip removal groove; the central symmetry of the drill tip part is provided with a main cutting edge; the main cutting edge is divided into a first blade surface and a second blade surface; the end, where the drill body part is connected with the drill tip part, is provided with a third blade surface and a secondary chip removal groove; the technical scheme provided by the application is provided with a structure design of "double chip removal grooves and multiple blade surfaces", which can significantly improve the chip removal efficiency and machining stability of the PCB drill.

Description

Technical Field

[0001] This application relates to the field of PCB drill bit technology, and more particularly to a high chip removal PCB drill bit. Background Technology

[0002] As PCBs become increasingly smaller and thinner, denser glass fibers and insulating resins are used inside the boards to ensure rigidity and heat resistance. This increases the processing difficulty of the drill bit during drilling. In addition, chip removal is also an unavoidable problem in PCB drilling. Accumulated chips can hinder the normal feed of the drill bit, causing uneven force on the drill bit and making it prone to deflection, which affects the positional accuracy of the drilling. Furthermore, residual chips can rub and squeeze against the hole wall, causing the hole wall to become rough, scratched, burred, or even "roughened". In severe cases, it may even cause the hole wall to deform. Utility Model Content

[0003] The purpose of this application is to provide a PCB drill bit with high chip removal to solve at least one of the above-mentioned technical problems.

[0004] To solve the above-mentioned technical problems, this application provides a high chip removal PCB drill bit, including a drill body, the drill body having a drill tip and a drill body at its ends, and a first chip removal groove extending axially around the drill body is formed on the drill body, the first chip removal groove extending from the drill tip to the drill body.

[0005] A second chip removal groove is formed within the first chip removal groove, and the second chip removal groove extends spirally around the axial direction of the drill body body;

[0006] The drill tip has a centrally symmetrical main cutting edge, which is divided into a first cutting edge and a second cutting edge; the drill body has a third cutting edge and a secondary chip removal groove at the end where it connects to the drill tip.

[0007] In the aforementioned implementation process, this solution significantly improves the chip removal efficiency and processing stability of PCB drill bits through a structural design of "dual chip removal grooves + multi-edge surface collaboration." Specifically, the first chip removal groove extends from the drill tip to the drill body, providing the main chip removal channel. The second chip removal groove added within the first chip removal groove forms a "groove within a groove" structure, which can divert chips—when chips generated by the drill tip enter the first chip removal groove, some fine chips can be quickly discharged through the second chip removal groove, avoiding the clogging problem caused by chip accumulation in a single chip removal groove. At the same time, the first and second cutting edges formed by the separation of the main cutting edge can optimize the cutting angle, reduce the contact resistance between the drill tip and the PCB board (including compacted glass fiber and insulating resin), make the chips more regular, and reduce the probability of chip adhesion. The third cutting edge and the secondary chip removal groove at the connection end between the drill body and the drill tip further assist in chip removal, preventing chip retention at the junction of the drill tip and the drill body. This multi-structure collaborative design effectively solves the problems of drilling deviation, rough hole wall, and "roughness" caused by poor chip removal in traditional drill bits. While ensuring drilling position accuracy, it significantly improves the smoothness of the hole wall, making it particularly suitable for high-precision processing scenarios of miniaturized and thin PCBs.

[0008] Preferably, the bottom angle of the secondary chip removal groove near the third cutting edge is α, and α satisfies 68°<α<72°;

[0009] In the above implementation process, the bottom angle α of the secondary chip removal groove near the third cutting edge is limited to 68° < α < 72°. This angle range achieves a balance between chip removal efficiency and structural strength. If α ≤ 68°, the bottom angle is too small, which will cause the groove opening of the secondary chip removal groove to narrow, and the chips are easily stuck during the discharge process. This is especially true when processing PCB boards containing high-hardness glass fibers, where large chips are more likely to block the channel. If α ≥ 72°, the resulting cutting edge sharpness is not obvious, and the cutting performance is weakened.

[0010] Preferably, the groove depth of the second chip removal groove does not exceed 5% of the maximum diameter of the drill body.

[0011] In the above implementation process, limiting the groove depth ratio of the second chip removal groove to no more than 5% of the maximum diameter of the drill body ensures the overall structural strength of the drill body while enhancing chip removal functionality. If the depth ratio exceeds 5%, the excessive depth of the second chip removal groove will significantly weaken the wall thickness of the first chip removal groove, causing radial deformation of the drill body due to insufficient rigidity during high-speed rotation. This is especially problematic when machining thick PCB boards, where the drill bit is prone to wobble, affecting drilling accuracy. Furthermore, excessively deep grooves may cause chips to become stuck during discharge due to insufficient wall support, thus reducing chip removal efficiency. When the depth ratio is ≤5%, the second chip removal groove provides an additional chip removal channel, diverting some chips (especially fine debris) from the first chip removal groove to prevent congestion in a single channel. It also ensures the torsional strength and wear resistance of the drill body, making it suitable for high-resistance machining scenarios involving dense glass fibers in PCB boards. This design balances the dual requirements of "efficient chip removal" and "structural stability," extending drill bit lifespan and reducing processing interruptions caused by structural failure.

[0012] Preferably, the spiral angle of the first chip removal groove and the second chip removal groove is 25°-45°;

[0013] In the above implementation process, the helix angles of the first and second chip removal grooves are limited to 25°-45°, which can be flexibly adapted to the chip removal speed and cutting resistance according to the characteristics of the PCB board. The helix angle is a key parameter affecting chip removal efficiency: if the angle is <25°, the helix angle is too small, the chips rise slowly along the groove wall, and are prone to accumulate in the groove. Especially during high-speed drilling, the accumulated chips will increase the friction between the drill bit and the hole wall, leading to increased hole wall temperature and resin melting and adhesion; if the angle is >45°, the helix angle is too large. Although the chip removal speed is faster, the contact area between the drill bit and the board increases, the cutting resistance increases sharply, and the drill bit is prone to vibration, resulting in decreased hole position accuracy and even drill bit breakage. The 25°-45° range can be adjusted according to the thickness and material (such as glass fiber content) of the PCB board: when processing thinner boards, a larger angle is used to increase the chip removal speed; when processing thicker boards, a smaller angle is used to balance resistance and chip removal. This adaptive design ensures that chips can be quickly discharged and the drill bit is under stable force in different processing scenarios, effectively reducing defects such as rough hole walls and "roughness" and improving processing efficiency.

[0014] Preferably, the drill body is made of cemented carbide material;

[0015] In the aforementioned process, the drill body is made of cemented carbide, which significantly improves the drill bit's wear resistance and cutting performance, perfectly meeting the demanding processing requirements of PCB boards. Traditional high-speed steel drill bits, when processing PCB boards containing high-hardness glass fibers and compact insulating resin, are prone to reduced drilling accuracy and rough hole walls due to cutting edge wear, resulting in a short service life. Cemented carbide (such as WC-Co alloy) possesses extremely high hardness (HRA 89-93) and wear resistance, allowing its cutting edge to remain sharp for extended periods. During high-speed drilling, it effectively cuts glass fiber bundles, reducing the "extrusion" processing caused by cutting edge dulling (which easily leads to hole wall cracking and burrs). Simultaneously, cemented carbide has high compressive strength, capable of withstanding the instantaneous impact forces generated by material inhomogeneity during PCB processing, reducing the risk of drill bit bending or breakage. Furthermore, cemented carbide has better thermal conductivity than high-speed steel, quickly dissipating cutting heat and preventing PCB resin melting and chip adhesion due to localized high temperatures, further ensuring smooth chip removal. This material selection fundamentally solves the problems of traditional drill bits being "easy to wear, short lifespan, and poor processing quality," making it especially suitable for high-precision, high-volume processing scenarios of miniaturized PCBs.

[0016] Preferably, the tip angle of the drill bit is 135°-160°;

[0017] In the above implementation process, the drill tip angle is limited to 135°-160°, optimizing the drill bit's cutting performance and positioning accuracy, and adapting to the compact structural characteristics of PCB boards. The angle directly affects the cutting force and cutting stability of the drill tip: if the angle is <135°, the drill tip is too sharp, resulting in low cutting resistance but insufficient cutting edge strength, making it prone to chipping when contacting high-hardness glass fibers; simultaneously, an angle that is too small leads to poor drill tip center positioning and easy deflection. If the angle is >160°, the drill tip is too blunt, requiring greater axial force during cutting, which will compress the PCB board, causing hole deformation, resin layer cracking, and irregular chip formation, increasing the difficulty of chip removal. The 135°-160° angle range ensures that the drill tip has sufficient cutting edge strength to resist the impact of glass fibers, while achieving "smooth cutting" through a reasonable cutting angle—the drill tip center first contacts the board to form a positioning point, and the main cutting edge gradually unfolds to cut, reducing vibration during cutting. This design significantly improves the positional accuracy of drilling, avoids hole cracking and deflection, and makes the chips form more regularly. Combined with the chip removal groove design, it further improves chip removal efficiency.

[0018] Preferably, it also includes a fixing rod connected to the drill body body, and the fixing rod has an installation groove formed on it.

[0019] Compared with existing technologies, the beneficial effects of this application are as follows: This solution significantly improves the chip removal efficiency and processing stability of PCB drill bits through a structural design of "dual chip removal grooves + multi-edge surface collaboration". Specifically, the first chip removal groove extends from the drill tip to the drill body, providing a main chip removal channel for the chips. The second chip removal groove added within the first chip removal groove forms a "groove within a groove" structure, which can divert the chips. When the chips generated by the cutting at the drill tip enter the first chip removal groove, some small chips can be quickly discharged through the second chip removal groove, avoiding the clogging problem caused by chip accumulation in a single chip removal groove. At the same time, the first and second cutting edges formed by the separation of the main cutting edge can optimize the cutting angle, reduce the contact resistance between the drill tip and the PCB board (including compacted glass fiber and insulating resin), make the chips more regular, and reduce the probability of chip adhesion. The third cutting edge and the secondary chip removal groove at the connection end between the drill body and the drill tip further assist in chip removal and prevent chip retention at the junction of the drill tip and the drill body. This multi-structure collaborative design effectively solves the problems of drilling deviation, rough hole wall, and "roughness" caused by poor chip removal in traditional drill bits. While ensuring the accuracy of drilling position, it significantly improves the smoothness of hole wall, making it particularly suitable for high-precision processing scenarios of miniaturized and thin PCBs. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application 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 some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the overall structure of one embodiment of this application;

[0022] Figure 2 This is a structural schematic diagram of the drill bit end face from one embodiment of this application;

[0023] Figure 3 yes Figure 2 Enlarged structural diagram of section A;

[0024] Figure 4 This is a schematic diagram of the end portion structure of the drill bit body according to one embodiment of this application;

[0025] Wherein: 10, drill tip; 11, main cutting edge; 12, first cutting edge; 13, second cutting edge; 14, secondary chip removal groove; 15, groove bottom angle; 16, third cutting edge; 20, drill body; 21, first chip removal groove; 22, second chip removal groove; 30, fixing rod; 31, mounting groove. Detailed Implementation

[0026] The following drawings disclose several embodiments of this application. For clarity, many practical details will be described in the following description. However, it should be understood that these practical details should not be used to limit this application. That is, in some embodiments of this application, these practical details are not essential. In addition, for the sake of simplicity, some conventional structures and components will be shown in the drawings in a simple schematic manner.

[0027] It should be noted that all directional indications in the embodiments of this application, such as up, down, left, right, front, back, etc., are only used to explain the relative positional relationship and movement of the components in a specific posture as shown in the attached figure. If the specific posture changes, the directional indication will also change accordingly.

[0028] Furthermore, the use of terms such as "first" and "second" in this application is for descriptive purposes only and does not specifically refer to any order or sequence, nor is it intended to limit this application. They are merely used to distinguish components or operations described using the same technical terms and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of various embodiments can be combined with each other, but only if they are feasible for those skilled in the art. If a combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0029] To further understand the utility model content, features, and effects of this application, the following embodiments are provided, and detailed descriptions are given below in conjunction with the accompanying drawings: Example

[0030] As PCBs become increasingly miniaturized and thinner, denser glass fibers and insulating resins are used inside the boards to ensure rigidity and heat resistance. This increases the processing difficulty of the drill bit during drilling. In addition, chip removal is a persistent problem in PCB drilling. Accumulated chips hinder the normal feed of the drill bit, causing uneven force and potential deflection, affecting drilling accuracy. Furthermore, residual chips rub and compress against the hole wall, resulting in roughness, scratches, burrs, and even "roughening," which can lead to deformation in severe cases. To address these technical problems, this embodiment provides the following technical solution:

[0031] For details, please see Figure 1-4This embodiment provides a high chip removal PCB drill bit, including a drill body body, the drill body body ends with a drill tip 10 and a drill body 20, and a first chip removal groove 21 is formed on the drill body body, extending axially spirally around the drill body body, the first chip removal groove 21 extends from the drill tip 10 to the drill body 20.

[0032] Furthermore, a second chip removal groove 22 is formed within the first chip removal groove 21, and the second chip removal groove 22 is formed by spirally extending around the axial direction of the drill body body.

[0033] Specifically, the drill tip 10 has a centrally symmetrical main cutting edge 11, which is divided into a first cutting surface 12 and a second cutting surface 13; the drill body 20 has a third cutting surface 16 and a secondary chip removal groove 14 at the end where it is connected to the drill tip 10.

[0034] In the above solution, the "dual chip removal groove + multi-edge synergy" structural design significantly improves the chip removal efficiency and processing stability of PCB drill bits. Specifically, the first chip removal groove 21 extends from the drill tip 10 to the drill body 20, providing the main chip removal channel. The second chip removal groove 22 added within the first chip removal groove 21 forms a "groove within a groove" structure, which can divert the chips. When the chips generated by the cutting of the drill tip 10 enter the first chip removal groove 21, some small chips can be quickly discharged through the second chip removal groove 22, avoiding the clogging problem caused by chip accumulation in a single chip removal groove. Meanwhile, the first cutting edge 12 and the second cutting edge 13 formed by the separation of the main cutting edge 11 can optimize the cutting angle, reduce the contact resistance between the drill tip 10 and the PCB board (containing compacted glass fiber and insulating resin), make the chips more regular, and reduce the probability of chip adhesion. The third cutting edge 16 and the secondary chip removal groove 14 at the connection end between the drill body 20 and the drill tip 10 further assist in chip removal and prevent chip retention at the junction of the drill tip 10 and the drill body 20. This multi-structure collaborative design effectively solves the problems of drilling deviation, rough hole wall, and "roughness" caused by poor chip removal in traditional drill bits. While ensuring the drilling position accuracy, it significantly improves the hole wall smoothness, and is especially suitable for high-precision processing scenarios of miniaturized and thin PCBs.

[0035] Specifically, the bottom angle 15 of the secondary chip removal groove 14 near the third cutting edge 16 is α, and α satisfies 68°<α<72°;

[0036] In the above design, the bottom angle 15 α of the secondary chip removal groove 14 near the third cutting edge 16 is limited to 68° < α < 72°. This angle range achieves a balance between chip removal efficiency and structural strength. If α ≤ 68°, the bottom angle 15 is too small, which will cause the groove opening of the secondary chip removal groove 14 to narrow, and the chips will easily get stuck during the discharge process. Especially when processing PCB boards containing high-hardness glass fibers, large chips are more likely to block the channel. If α ≥ 72°, the sharpness of the resulting cutting edge is not obvious, and the cutting performance is weakened.

[0037] Specifically, the groove depth ratio of the second chip removal groove 22 shall not exceed 5% of the maximum diameter of the drill body;

[0038] In the above scheme, limiting the groove depth ratio of the second chip removal groove 22 to no more than 5% of the maximum diameter of the drill body can enhance the chip removal function while ensuring the overall structural strength of the drill body. If the depth ratio exceeds 5%, the excessive depth of the second chip removal groove 22 will significantly weaken the wall thickness of the first chip removal groove 21, causing radial deformation of the drill body 20 due to insufficient rigidity during high-speed rotation. Especially when processing thick PCB boards, the drill bit is prone to wobble, affecting drilling accuracy. At the same time, excessively deep grooves may also cause chips to get stuck during the discharge process due to insufficient groove wall support, which will reduce chip removal efficiency. When the depth ratio is ≤5%, the second chip removal groove 22 can provide an additional chip removal channel to divert some of the chips (especially small debris) in the first chip removal groove 21, avoiding congestion in a single channel, while ensuring the torsional strength and wear resistance of the drill body, making it suitable for high-resistance processing scenarios of dense glass fibers in PCB boards. This design balances the dual requirements of "efficient chip removal" and "structural stability," extending the lifespan of the drill bit and reducing processing interruptions caused by structural failure.

[0039] Specifically, the helical angles of the first chip removal groove 21 and the second chip removal groove 22 are 25°-45°;

[0040] In the above scheme, the helix angles of the first chip removal groove 21 and the second chip removal groove 22 are limited to 25°-45°, which can be flexibly adapted to the chip removal speed and cutting resistance according to the characteristics of the PCB board. The helix angle is a key parameter affecting chip removal efficiency: if the angle is <25°, the helix angle is too small, the chips rise slowly along the groove wall, and are easy to accumulate in the groove. Especially during high-speed drilling, the accumulated chips will increase the friction between the drill bit and the hole wall, resulting in increased hole wall temperature and resin melting and adhesion; if the angle is >45°, the helix angle is too large. Although the chip removal speed is faster, the contact area between the drill bit and the board increases, the cutting resistance increases sharply, which can easily cause drill bit vibration, resulting in decreased hole position accuracy, or even drill bit breakage. The range of 25°-45° can be adjusted according to the thickness and material (such as glass fiber content) of the PCB board: when processing thinner boards, a larger angle is used to increase the chip removal speed; when processing thicker boards, a smaller angle is used to balance resistance and chip removal. This adaptive design ensures that chips can be quickly discharged and the drill bit is under stable force in different processing scenarios, effectively reducing defects such as rough hole walls and "roughness" and improving processing efficiency.

[0041] Specifically, the drill body is made of cemented carbide material;

[0042] In the above solution, the drill body is made of cemented carbide, which significantly improves the drill bit's wear resistance and cutting performance, perfectly meeting the high-difficulty processing requirements of PCB boards. Traditional high-speed steel drill bits are prone to reduced drilling accuracy and rough hole walls due to cutting edge wear when processing PCB boards containing high-hardness glass fibers and compact insulating resin, and also have a short service life. Cemented carbide (such as WC-Co alloy) has extremely high hardness (HRA 89-93) and wear resistance, and its cutting edge can remain sharp for a long time. During high-speed drilling, it can effectively cut glass fiber bundles, reducing the "extrusion" processing caused by cutting edge dulling (which easily leads to hole wall cracking and burrs). At the same time, cemented carbide has high compressive strength, which can withstand the instantaneous impact force generated by material inhomogeneity during PCB processing, reducing the risk of drill bit bending or breakage. Furthermore, cemented carbide has better thermal conductivity than high-speed steel, which can quickly conduct cutting heat away, preventing PCB resin from melting and sticking to chips due to localized high temperatures, further ensuring smooth chip removal. This material selection fundamentally solves the problems of traditional drill bits being "easy to wear, short lifespan, and poor processing quality," making it especially suitable for high-precision, high-volume processing scenarios of miniaturized PCBs.

[0043] Specifically, the angle of the drill tip 10 is 135°-160°;

[0044] In the above implementation process, the angle of the drill tip 10 is limited to 135°-160°, which optimizes the drill bit's cutting performance and positioning accuracy, and adapts to the compact structural characteristics of the PCB board. The angle directly affects the cutting force and cutting stability of the drill tip 10: if the angle is <135°, the drill tip is too sharp, although the cutting resistance is small, the cutting edge strength is insufficient, and it is easy to chip when contacting high-hardness glass fiber; at the same time, too small an angle will lead to poor positioning of the drill tip center and easy deviation. If the angle is >160°, the drill tip is too blunt, requiring a larger axial force during cutting, which will squeeze the PCB board, causing hole deformation, resin layer cracking, and irregular chip formation, increasing the difficulty of chip removal. The angle range of 135°-160° can ensure that the drill tip 10 has sufficient cutting edge strength to resist the impact of glass fiber, and can achieve "smooth cutting" through a reasonable cutting angle - the center of the drill tip first contacts the board to form a positioning point, and the main cutting edge 11 gradually unfolds to cut, reducing vibration during cutting. This design significantly improves the positional accuracy of drilling, avoids hole cracking and deflection, and makes the chips form more regularly. Combined with the chip removal groove design, it further improves chip removal efficiency.

[0045] Specifically, it also includes a fixing rod 30 connected to the main body of the drill body, and the fixing rod 30 has an installation groove 31 formed on it.

[0046] The above description is merely a preferred embodiment of this application and is not intended to limit this application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application shall fall within the scope of the technical solution of this application.

Claims

1. A high-chip-discharge PCB drill bit, characterized in that: The drill body includes a drill body body, the drill body body having a drill tip and a drill body at its ends. A first chip removal groove is formed on the drill body body, extending axially and spirally around the drill body body. The first chip removal groove extends from the drill tip to the drill body. A second chip removal groove is formed within the first chip removal groove, and the second chip removal groove extends spirally around the axial direction of the drill body body; The drill tip has a centrally symmetrical main cutting edge, which is divided into a first cutting edge and a second cutting edge; the drill body and the drill tip are connected at one end to form a third cutting edge and a secondary chip removal groove.

2. The PCB drill bit according to claim 1, characterized in that: The bottom angle of the secondary chip removal groove near the third cutting edge is α, and α satisfies 68°<α<72°.

3. The PCB drill bit according to claim 1, characterized in that: The groove depth of the second chip removal groove shall not exceed 5% of the maximum diameter of the drill body.

4. The PCB drill bit according to claim 3, characterized in that: The spiral angles of the first chip removal groove and the second chip removal groove are 25°-45°.

5. The PCB drill bit according to any one of claims 1-4, characterized in that: The drill body is made of cemented carbide.

6. The PCB drill bit according to claim 5, characterized in that: The angle of the drill tip is 135°-160°.

7. The PCB drill bit according to claim 6, characterized in that: It also includes a fixing rod connected to the main body of the drill body, and the fixing rod has an installation groove formed on it.

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