PCB cemented carbide micro drill with good thermal stability

Abstract

The utility model discloses a PCB hard alloy micro drill with good thermal stability relates to the technical field of alloy drill bit, including outer tooth connector, tool holder, hollow nickel foam cover and outer tooth handle part, the bottom of tool holder is welded to the top of outer tooth connector, the top of tool holder is provided with cooling mechanism, the inside of cooling mechanism is provided with the inside of hollow nickel foam cover and is wrapped, utilizes the hollow nickel foam cover and passes the absorption coolant or moisture, and the temperature of outer tooth handle part is reduced through the evaporation heat dissipation, the inside of tool holder is provided with assembly mechanism, the inside of tool holder is positioned with outer tooth handle part and handles the processing of tool holder to outer tooth handle part and cooling mechanism and combines simultaneously. The hollow nickel foam cover is wrapped drill bit outer tooth handle part and carries out the cooling, is a kind of combination metal high thermal conductivity and porous structure evaporation cooling, and the hard plastic ring one side setting protruding piece of the bottom of hollow nickel foam cover is connected with the clamping groove inside tool holder and is handled.

Description

Technical Field

[0001] This utility model relates to the technical field of alloy drill bits, specifically to a PCB cemented carbide micro drill with good thermal stability. Background Technology

[0002] In printed circuit board manufacturing, the thermal stability of cemented carbide micro drills is a key performance indicator, directly affecting drilling accuracy, tool life, and processing efficiency.

[0003] Drill bits with poor thermal stability can cause a series of problems in PCB processing or other precision drilling scenarios, directly affecting processing quality, tool life and production efficiency. Drill bits are generally single-handle structures. When carbide micro drills are rotating, heat will accumulate on the surface of the drill bit, causing the drill bit temperature to rise quickly and making it difficult to cool down. Utility Model Content

[0004] The purpose of this invention is to provide a PCB cemented carbide micro-drill with good thermal stability to solve the above-mentioned defects caused by the prior art.

[0005] A PCB cemented carbide micro-drill with good thermal stability includes an external thread connector, a tool holder, a hollow nickel foam sleeve, and an external thread shank. The top of the external thread connector is welded to the bottom of the tool holder. A cooling mechanism is arranged directly above the tool holder. The external thread shank, which is located inside the cooling mechanism, is enclosed within the hollow nickel foam sleeve. The hollow nickel foam sleeve absorbs coolant or moisture and reduces the temperature of the external thread shank through evaporation. An assembly mechanism is arranged inside the tool holder. The assembly mechanism positions the external thread shank to the inner end of the tool holder and simultaneously connects the tool holder to the external thread shank and the cooling mechanism. The external thread shank and tool holder can then be separated and replaced according to usage requirements.

[0006] Preferably, the cooling mechanism includes positioning holes, a hard plastic ring, protrusions, fasteners, a hollow nickel foam sleeve, and a slot. The positioning holes are symmetrically opened on both sides of the tool holder. A hard plastic ring is provided inside the tool holder. Protrusions are symmetrically arranged on the outer side of the hard plastic ring. A fastener is threaded to one side of each protrusion. A hollow nickel foam sleeve is provided directly above the hard plastic ring. The slots are symmetrically opened at the inner end of the tool holder. The inner end of the hollow nickel foam sleeve wraps around the external thread shank.

[0007] Preferably, the hollow nickel foam sleeve is connected to the outside of the slot via symmetrically arranged protrusions on the outside, and the protrusions are connected to the positioning hole via fasteners.

[0008] Preferably, the assembly mechanism includes a tool holder, a limiting ring, a drill bit, a chip removal groove, an external shank, a backlash washer, and an internal shank positioning seat. The tool holder is provided with a limiting ring, the drill bit is welded to the inner end of the limiting ring, the external shank is welded to the bottom end of the drill bit, the external shank is disposed inside the tool holder, the backlash washer is fitted onto the outer side of the external shank, the internal shank positioning seat is connected to the outer side of the external shank, the internal shank positioning seat is welded to the inside of the tool holder, and the chip removal groove is spirally disposed on the outer side of the drill bit.

[0009] Preferably, the tool holder is connected to the outer side of the external shank via an internally provided internal tooth positioning seat.

[0010] Preferably, the drill bit is connected to the internal tooth positioning seat via an external tooth shank welded to the tail end.

[0011] Compared with the prior art, the present invention has the following advantages:

[0012] 1. The drill bit's external shank is cooled by wrapping it with a hollow nickel foam sleeve. This method combines the high thermal conductivity of metal with the evaporative cooling of a porous structure. The sleeve is mechanically interlocked by a groove inside the tool holder and a protrusion on one side of the hard plastic ring at the bottom of the hollow nickel foam sleeve. This integrated design allows for quick installation and removal without disrupting the dynamic balance.

[0013] 2. The internal thread of the internal thread positioning seat is screwed into the external thread shank at the tail end of the drill bit. The drill bit is tightened by the thread preload. The limiting ring on the outside of the drill bit contacts the top plane of the tool holder, which restricts the axial movement of the drill bit, shares the radial load during cutting, and reduces the bending deformation of the drill bit. The dual positioning of thread axial locking and limiting ring radial support, as well as the material hardness difference between the hard plastic ring and the metal tool holder, can absorb high-frequency harmonics, which significantly improves the rigidity and stability of the drill bit. Attached Figure Description

[0014] Figure 1 This is a three-dimensional structural diagram of the present invention.

[0015] Figure 2 This is a front view schematic diagram of the assembly mechanism in this utility model.

[0016] Figure 3 This is a side view of the hollow nickel foam sleeve structure in this utility model.

[0017] Figure 4 This is a top view of the tool holder structure in this utility model.

[0018] Figure 5 This is a schematic diagram of the orthographic structure of the tool holder in this utility model.

[0019] in:

[0020] 1. External thread connector; 2. Tool holder; 3. Positioning hole; 4. Cooling mechanism; 5. Limiting ring; 6. Drill bit; 7. Chip removal groove; 8. Assembly mechanism; 9. Hard plastic ring; 10. Protrusion; 11. Fastener; 12. Hollow nickel foam sleeve; 13. External thread shank; 14. Slot; 15. Anti-reverse washer; 16. Internal thread positioning seat. Detailed Implementation

[0021] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the present utility model will be further described below in conjunction with specific embodiments.

[0022] like Figures 1 to 5 As shown, a PCB cemented carbide micro-drill with good thermal stability includes an external thread connector 1, a tool holder 2, a hollow nickel foam sleeve 12, and an external thread shank 13. The top of the external thread connector 1 is welded to the bottom of the tool holder 2. A cooling mechanism 4 is arranged directly above the tool holder 2. The external thread shank 13 is enclosed inside the hollow nickel foam sleeve 12. The hollow nickel foam sleeve 12 absorbs coolant or moisture and reduces the temperature of the external thread shank 13 through evaporation. An assembly mechanism 8 is arranged inside the tool holder 2. The assembly mechanism 8 positions the external thread shank 13 to the inner end of the tool holder 2. At the same time, the tool holder 2 combines the external thread shank 13 and the cooling mechanism 4. Then, the external thread shank 13 and the tool holder 2 can be separated and replaced according to the needs of use.

[0023] In this embodiment, the cooling mechanism 4 includes a positioning hole 3, a hard plastic ring 9, a protrusion 10, a fastener 11, a hollow nickel foam sleeve 12, and a slot 14. The positioning hole 3 is symmetrically opened on both sides of the tool holder 2. The tool holder 2 is provided with a hard plastic ring 9 inside. The outer side of the hard plastic ring 9 is symmetrically provided with a protrusion 10. One side of the protrusion 10 is threadedly connected to a fastener 11. The hollow nickel foam sleeve 12 is provided directly above the hard plastic ring 9. The slot 14 is symmetrically opened at the inner end of the tool holder 2. The inner end of the hollow nickel foam sleeve 12 wraps around the external shank portion 13. The hollow nickel foam sleeve 12 covers and cools a part of the external shank portion 13, while preventing the internal coolant of the hollow nickel foam sleeve 12 from flowing out due to rotation.

[0024] In this embodiment, the hollow nickel foam sleeve 12 is connected to the outer side of the slot 14 by symmetrically arranged protrusions 10 on the outer side. The protrusions 10 and the positioning hole 3 are connected by fasteners 11. The bottom end of the hollow nickel foam sleeve 12 is positioned by the protrusions 10 and the fasteners 11, which facilitates the disassembly and assembly of the hollow nickel foam sleeve 12.

[0025] In this embodiment, the assembly mechanism 8 includes a tool holder 2, a limiting ring 5, a drill bit 6, a chip removal groove 7, an external shank 13, a backlash washer 15, and an internal shank positioning seat 16. The tool holder 2 is provided with a limiting ring 5, and the drill bit 6 is welded to the inner end of the limiting ring 5. The external shank 13 is welded to the bottom end of the drill bit 6. The external shank 13 is disposed inside the tool holder 2. The backlash washer 15 is fitted onto the outer side of the external shank 13. The external shank 13 is connected to the outer side of the external shank 13. The internal shank positioning seat 16 is welded to the inside of the tool holder 2. The chip removal groove 7 is spirally disposed on the outer side of the drill bit 6. The external shank 13 is wrapped by a hollow nickel foam sleeve 12, so that the liquid and the external shank 13 are cooled down.

[0026] In this embodiment, the tool holder 2 is connected to the outer side of the external tooth shank 13 through an internal tooth positioning seat 16, and is positioned by a portion of the tail end of the internal tooth positioning seat 16 connected to the external tooth shank 13.

[0027] In this embodiment, the drill bit 6 is connected to the internal tooth positioning seat 16 via the external tooth shank 13 welded to the tail end, and is connected to the interior of the tool holder 2 via the external tooth shank 13 at the bottom end of the drill bit 6, thereby improving the stability of the drill bit 6 during rotation and cooling by the tool holder 2.

[0028] In practical applications, this type of PCB carbide micro-drill with good thermal stability includes the following tasks:

[0029] Step 1: Before use, first clean the hollow nickel foam sleeve 12 with acetone, then immerse the hollow nickel foam sleeve 12 in coolant. Then, vacuum the hollow nickel foam sleeve 12 with a vacuum machine for 5 minutes. Repeat this process three times. Then, install the hard plastic ring 9 at the bottom of the hollow nickel foam sleeve 12 into the inside of the tool holder 2, so that the symmetrically arranged slots 14 inside the tool holder 2 are connected to the protrusions 10 on the outside of the hard plastic ring 9. Then, insert the fasteners 11 into the positioning holes 3 to lock the tool holder 2 and the protrusions 10.

[0030] Step 2: The operator first puts the anti-reverse washer 15 into the root of the thread of the external shank 13, close to the shoulder of the drill bit 6, with the serrated surface of the anti-reverse washer 15 facing the tightening direction of the thread of the external shank 13. The internal thread of the internal thread positioning seat 16 is screwed into the external shank 13 to press the anti-reverse washer 15, thereby connecting the internal thread positioning seat 16 set inside the tool holder 2 with the tail end of the drill bit 6. At the same time, the limiting ring 5 set on the outside of the drill bit 6 fits against the top of the tool holder 2, thereby completing the support and positioning of the drill bit 6.

[0031] Step 3: The hollow nickel foam sleeve 12 is wrapped around the bottom end of the drill bit 6. The external thread connector 1 at the bottom end of the tool holder 2 is connected to the bottom end of the spindle. The spindle drives the tool holder 2 and the drill bit 6 to rotate. The drill bit 6 drills holes on the surface of the PCB board. At the same time, the coolant stored in the foam pores inside the hollow nickel foam sleeve 12 evaporates when heated. When the drill bit 6 rotates at high speed, the centrifugal force atomizes the coolant and sprays it onto the external thread shank 13 to enhance convection heat dissipation.

[0032] Step 4: During the drilling process, the metal and non-metal chips generated by the drill bit 6 through the spirally distributed chip removal grooves 7 on the outside are quickly discharged from the hole to avoid blockage. At the same time, the coolant stored in the pores inside the hollow nickel foam sleeve 12 absorbs a large amount of heat when it evaporates, further suppressing the temperature rise. The high temperature zone of the drill bit 6 is diffused to the external shank 13, and the temperature distribution of the drill tip is uniform.

[0033] Therefore, the above-disclosed embodiments are merely illustrative in all respects and are not the only ones. All modifications within the scope of this utility model or its equivalents are included in this utility model.

Claims

1. A PCB cemented carbide micro-drill with good thermal stability, characterized in that: The device includes an external thread connector (1), a tool holder (2), a hollow nickel foam sleeve (12), and an external thread shank (13). The top of the external thread connector (1) is welded to the bottom of the tool holder (2). A cooling mechanism (4) is provided directly above the tool holder (2). The external thread shank (13) inside the cooling mechanism (4) is wrapped with the inside of the hollow nickel foam sleeve (12). The hollow nickel foam sleeve (12) absorbs coolant or water and cools down the external thread shank (13) by evaporation. An assembly mechanism (8) is provided inside the tool holder (2). The assembly mechanism (8) positions the external thread shank (13) and the inner end of the tool holder (2). At the same time, the tool holder (2) combines the external thread shank (13) and the cooling mechanism (4). Then, the external thread shank (13) and the tool holder (2) can be separated and replaced according to the needs of use.

2. The PCB cemented carbide micro-drill with good thermal stability according to claim 1, characterized in that: The cooling mechanism (4) includes a positioning hole (3), a hard plastic ring (9), a protrusion (10), a fastener (11), a hollow nickel foam sleeve (12), and a slot (14). The positioning hole (3) is symmetrically opened on both sides of the tool holder (2). The tool holder (2) is provided with a hard plastic ring (9) inside. The outer side of the hard plastic ring (9) is symmetrically provided with a protrusion (10). One side of the protrusion (10) is threaded with a fastener (11). The hollow nickel foam sleeve (12) is provided directly above the hard plastic ring (9). The slot (14) is symmetrically opened at the inner end of the tool holder (2). The inner end of the hollow nickel foam sleeve (12) is wrapped with an external tooth shank (13).

3. The PCB cemented carbide micro-drill with good thermal stability according to claim 2, characterized in that: The hollow nickel foam sleeve (12) is connected to the outside of the slot (14) by symmetrically arranged protrusions (10) on the outside, and the protrusions (10) and the positioning hole (3) are connected by fasteners (11).

4. The PCB cemented carbide micro-drill with good thermal stability according to claim 1, characterized in that: The assembly mechanism (8) includes a tool holder (2), a limiting ring (5), a drill bit (6), a chip removal groove (7), an external shank (13), a backlash washer (15), and an internal shank positioning seat (16). The tool holder (2) is provided with a limiting ring (5). The drill bit (6) is welded to the inner end of the limiting ring (5). The external shank (13) is welded to the bottom end of the drill bit (6). The external shank (13) is located inside the tool holder (2). The backlash washer (15) is fitted onto the outer side of the external shank (13). The external shank (13) is connected to the outer side of the external shank (13). The internal shank positioning seat (16) is welded to the inside of the tool holder (2). The chip removal groove (7) is spirally arranged on the outer side of the drill bit (6).

5. A PCB cemented carbide micro-drill with good thermal stability according to claim 4, characterized in that: The tool holder (2) is connected to the outside of the external tooth shank (13) through an internal tooth positioning seat (16).

6. The PCB cemented carbide micro-drill with good thermal stability according to claim 4, characterized in that: The drill bit (6) is connected to the internal tooth positioning seat (16) via an external tooth shank (13) welded to the tail end.

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