A cutting head drill

Abstract

This invention belongs to the technical field of cutting machine equipment, and particularly relates to a cutting head drill. This invention provides a cutting head drill, including a drill tip cutting section, a heat-conducting section, a temperature-regulating spindle, and a self-circulating heat dissipation structure. This allows the drill to conduct heat generated near the drill tip to a location away from the drill tip during high-speed rotating drilling, and dissipate the heat through airflow generated by the drill's own rotation. This solves the problem of edge melting during fabric drilling. Furthermore, it allows the thermal state of the drilling end to remain stable during drilling, making it suitable for various fabrics to form stable and identifiable hole marks.

Description

Technical Field

[0001] This invention belongs to the technical field of cutting machine equipment, and particularly relates to a cutting head drill. Background Technology

[0002] Cutting tables are typically equipped with cutting tools and punching tools. While cutting the fabric outline, they simultaneously punch positioning holes for subsequent sewing. These positioning holes serve various purposes, including providing a positioning reference for the sewing machine, pre-positioning buttons or zippers, and marking alignment between multiple layers of fabric. Currently, the most commonly used punching tool in the industry is the drill bit. However, drill bits have a significant problem during operation: when the drill bit rotates at high speed and presses against the fabric for cutting, the heat generated is difficult to dissipate effectively. This is especially true for synthetic fiber fabrics such as nylon and polyester. When the drill tip temperature reaches or exceeds these melting points, the fibers around the hole melt rapidly. The molten polymer cools and re-solidifies after the drill bit is removed, forming a hard plastic ring around the hole.

[0003] To address the problem of drill bit overheating, current methods include external compressed air cooling, additional coolant circulation systems, and coating the drill bit surface with a heat-resistant coating. For example, Chinese invention patent CN102806376A discloses a drill bit that uses a heat pipe as a heat dissipation mechanism. Its main features include: a slot with an opening coaxial with the drill bit located at the top of the drill shank end and the bottom of the slot near the cutting edge; a plug at the opening of the slot to seal it, creating a cavity inside the drill bit. This vacuum-sealed cavity contains a low-boiling-point heat transfer medium.

[0004] The general structural principle of the drill bit in this invention patent is as follows: heat pipe technology is used to reduce the temperature of the cutting part of the drill bit and the surface of the workpiece.

[0005] However, the existing technology still has the following shortcomings in practical use, which are the technical problems that this invention aims to solve: 1. In drilling metals, composites, stone, etc., the focus is on hole diameter accuracy, surface quality, tool life, chip removal, and thermal damage control. However, the cutting bed drill bit is used on flexible fabrics, and different fabrics have different requirements for the thermal state of the drill bit, so it cannot be directly applied; 2. An external cooling medium needs to be introduced; 3. Simple cooling cannot stabilize and control the thermal state of the drill bit tip.

[0006] In conclusion, it is necessary to develop a drill bit that can be applied to cutting beds and has a stable control state to solve this problem. Summary of the Invention

[0007] This invention provides a cutting head drill, including a drill tip cutting part, a heat conduction part, a temperature control spindle, and a self-circulating heat dissipation structure. This allows the drill to conduct heat generated near the drill tip to a location away from the drill tip during high-speed rotating drilling, and dissipate the heat through the airflow generated by the rotation of the drill itself. This solves the problem of melted edges when drilling fabric. Furthermore, it enables the thermal state of the drilling end to remain stable during the drilling process, making it suitable for various fabrics to form stable and identifiable hole marks.

[0008] This invention overcomes the shortcomings of the prior art and provides a cutting head drill, comprising: a drill tip cutting part located at the lower end of the drill for contacting and penetrating the fabric; a heat-conducting part disposed at the upper end of the drill tip cutting part for transferring the heat generated by the drill tip cutting part upward; a temperature-regulating spindle including a shaft body disposed at the upper end of the heat-conducting part, a sealed cavity disposed inside the shaft body, and a working fluid encapsulated in the sealed cavity, the shaft body being divided into an evaporation section, a transition section, and a condensation section along the axial direction from bottom to top, and a liquid return structure disposed on the inner wall of the sealed cavity for returning the condensed working fluid to the evaporation section; a self-circulating heat dissipation structure including a finned disk fixed to the outer periphery of the condensation section and rotating coaxially with the shaft body; the heat-conducting part is a detachable structure including a thermal resistance block and a connecting handle disposed on the thermal resistance block and screwed to the lower end of the shaft body.

[0009] A further preferred technical solution is that the liquid return structure includes a capillary core layer attached to the inner wall of the sealed cavity and extending from the condensation section to the evaporation section.

[0010] A further preferred technical solution is that the liquid return structure further includes a spiral liquid guiding microgroove disposed on the inner wall of the sealed cavity, wherein the spiral direction of the spiral liquid guiding microgroove matches the rotation direction of the shaft.

[0011] A further preferred technical solution is that the liquid return structure further includes a liquid collection area disposed at the lower end of the condensation section for collecting the working liquid and guiding it to the spiral liquid guiding micro-channel.

[0012] A further preferred technical solution is that the self-circulating heat dissipation structure further includes a housing disposed on the shaft, an air guide shroud disposed on the inner wall of the housing, located above the finned disk and forming an air inlet, and an air outlet disposed through the housing near the outer end of the finned disk.

[0013] A further preferred technical solution is that the outlet of the air vent faces the direction of the tangent of the shaft.

[0014] A further preferred technical solution is that the drill tip cutting part and the heat-conducting part are connected by a low thermal resistance method, which is integrally processed, brazed, or interference-fitted.

[0015] A further preferred technical solution is that the finned disk includes a plurality of radial fins symmetrically distributed along the axis, and a guide angle is provided at the end of the radial fins.

[0016] A further preferred technical solution is that the working fluid is deionized water, ethanol, acetone, or a mixture thereof.

[0017] The beneficial effects of this invention are at least as follows: 1. It utilizes the power generated by the high-speed rotation of the drill bit for heat dissipation, without the need for any external cooling medium supply, which simplifies equipment configuration and reduces operating costs; 2. It effectively prevents the fibers at the hole edge from entering the molten state, thus avoiding the formation of molten edge defects; 3. It is not a single cooling device, but provides a more stable drill bit temperature state, and is applicable to a wider range of fabrics with different melting points. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a three-dimensional schematic diagram of the present invention; Figure 2 This is an exploded view of the present invention; Figure 3 This is a front sectional view of the present invention; Figure 4 This is a top sectional view of the present invention.

[0020] The meanings of the various reference numerals in the figure are as follows: 1. Drill tip cutting part; 2. Heat conduction part; 3. Temperature control spindle; 4. Self-circulating heat dissipation structure. Thermal resistance block 21, connecting handle 22, shaft 31, sealed cavity 32, working fluid 33, return fluid structure 34, finned disk 41, housing 42, air guide shroud 43, air outlet 44; Evaporation section 31a, transition section 31b, condensation section 31c, capillary core layer 341, liquid guiding microchannel 342, liquid collection area 343, radial fins 411. Detailed Implementation

[0021] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following description is only a preferred embodiment of the present invention and is not intended to limit the scope of the present invention.

[0022] The directional terms such as up, down, left, right, front, back, front, back, top, bottom, etc., mentioned or possibly mentioned in this specification are defined relative to the structure shown in the accompanying drawings. The terms "inner" and "outer" refer to the direction toward or away from the geometric center of a specific component, respectively. These are relative concepts and may therefore vary depending on their location and usage. Therefore, these or other directional terms should not be interpreted as restrictive terms.

[0023] As attached Figures 1-4 As shown, a cutting head drill includes: a drill tip cutting section 1, located at the lower end of the drill for contacting and penetrating fabric; a heat-conducting section 2, disposed at the upper end of the drill tip cutting section 1, for transferring the heat generated by the drill tip cutting section 1 upwards; and a temperature-regulating spindle 3, including a shaft body 31 disposed at the upper end of the heat-conducting section 2, a sealed cavity 32 disposed inside the shaft body 31, and a working fluid 33 encapsulated within the sealed cavity 32. The shaft body 31 is divided axially from bottom to top into sections... The sealed cavity 32 is divided into an evaporation section 31a, a transition section 31b, and a condensation section 31c. The inner wall of the sealed cavity 32 is provided with a return liquid structure 34 for returning the condensed working liquid 33 to the evaporation section 31a. The self-circulating heat dissipation structure 4 includes a finned disk 41 fixed to the outer periphery of the condensation section 31c and rotating coaxially with the shaft 31. The heat-conducting part 2 is a detachable structure, including a thermal resistance block 21 and a connecting handle 22 disposed on the thermal resistance block 21 and screwed to the lower end of the shaft 31.

[0024] This embodiment describes a basic type of cutting head drill, which, from bottom to top, includes: a drill tip cutting section, a heat-conducting section, a temperature-regulating spindle, and a self-circulating heat dissipation structure. The upper end of the drill is mounted on the rotating spindle or motor of the cutting bed. The drill tip cutting section 1, the heat-conducting section 2, and the temperature-regulating spindle 3 are arranged continuously along the same axis. The terms "upper" and "lower" are defined based on the working state of the drill after it is mounted on the cutting head. The end of the drill tip facing the fabric is the lower end, and the end facing away from the fabric and closer to the mounting end of the cutting head is the upper end. This drill does not have an external housing 42 and a wind guide shroud 43. It relies on the rotation of the finned disk 41 to refresh the surrounding air, and at the same time, it uses natural heat exchange to dissipate heat at the lower end. It is suitable for cutting equipment with limited space at the cutting head and where there is already some ventilation. The drill tip cutting section 1 is made of cemented carbide, and the end face is precision ground to ensure good thermal contact with the heat-conducting section. Since it performs both cutting and heat conduction functions, the thermal conductivity of the drill tip material should be set to no less than 50 W / (mK). The heat-conducting part 2 is located on the upper end of the drill tip cutting part 1 and is made of copper alloy. The heat-conducting part 2 includes a thermal resistance block 21 and a connecting handle 22. The thermal resistance block 21 and the drill tip cutting part 1 are integrally machined, meaning the front-end module is formed from the same material in one piece. The connecting handle 22 is located on the upper end of the thermal resistance block 21, with external threads machined on its outer surface. The lower end of the shaft 31 has a corresponding internal thread, the depth of which does not extend into the sealed cavity 32. During assembly, the user only needs to screw the connecting handle 22 axially into the lower end of the shaft 31. To ensure more stable assembly and interface heat transfer, an axial shoulder can be provided on the upper end of the connecting handle 22. After the connecting handle 22 is tightened, the shoulder presses against the lower end face of the shaft 31. The heat-conducting part 2 and the drill tip cutting part 1 are preferably replaced as a single front-end module. This maintains coaxiality and facilitates stable control of the heat conduction path. Thermal resistance blocks 21 with different thermal resistances can change the heat conduction state between the drill tip cutting part 1 and the evaporation section 31a to adapt to different fabrics.

[0025] The shaft 31 can be made of copper alloy, copper-clad steel composite, or a composite of stainless steel and a high thermal conductivity liner. Preferably, the outer layer of the shaft 31 is made of high-strength stainless steel, and the inner wall area is made of a high thermal conductivity material layer, or it can be made of integral copper alloy with a wear-resistant layer added to the outer surface. The shaft 31 is divided into three sections along the axial direction: evaporation section 31a, transition section 31b, and condensation section 31c. The length of the condensation section is 1.2 to 2.5 times the length of the evaporation section. The condensation section needs sufficient heat exchange area to dissipate heat, but should avoid excessively increasing the moment of inertia. The sealed cavity 32 is a cylindrical inner cavity formed along the central axis of the shaft 31. Both ends can be sealed by end sealing, vacuum brazing, electron beam welding, or laser welding. During assembly, the sealed cavity 32 is first evacuated, and then the working fluid 33 is filled into the sealed cavity 32. In this embodiment, the working fluid 33 is preferably deionized water, and the filling amount can be 20% to 55% of the effective volume of the sealed cavity 32. The finned disk 41 is installed on the outer periphery of the condenser section 31c and is made of aluminum alloy. It utilizes the rotation of the drill bit itself to ensure that the air in the condenser section is cooled more than the drill tip.

[0026] The working process of this embodiment is as follows: The user first screws the heat-conducting part 2 and the drill tip cutting part 1 into the lower end of the shaft 31. After the equipment starts to idle, the drill tip cutting part 1 and the heat-conducting part 2 rotate together with the shaft 31. When the drill bit comes into contact with the multi-layer fabric, the drill tip cutting part 1 generates heat first. The heat is transferred to the evaporation section 31a along the drill tip cutting part 1 and the heat-conducting part 2. The working liquid 33 in the evaporation section 31a absorbs heat and vaporizes. The steam flows upward along the sealed cavity 32 to the condensation section 31c. The condensation section 31c transfers heat to the finned disk 41. The finned disk 41 transfers heat to the surrounding air. The steam releases heat and becomes liquid. The liquid returns to the evaporation section 31a under the action of the liquid return structure 34, completing the heat dissipation of the drill bit front end.

[0027] A cooling method for a cutting head drill bit, using the cutting head drill bit described above, includes the following steps: the cutting part of the drill tip rotates at high speed and contacts the fabric to generate heat, the heat is transferred to the evaporation section via the heat-conducting transition section; the working fluid in the evaporation section absorbs heat and vaporizes into steam, the steam absorbs the latent heat of phase change and flows to the condensation section under the drive of the pressure difference; the steam releases latent heat in the condensation section and condenses into liquid, the condensed liquid returns to the evaporation section via the liquid return structure, forming a closed phase change heat transfer cycle; and the latent heat of the condensation section is transferred to the finned disk via the wall of the condensation section, the finned disk rotates with the shaft to drive air to flow along the surface of the condensation section and carry away the heat, and is then discharged through the exhaust duct.

[0028] As a preferred embodiment, the liquid return structure 34 includes a capillary core layer 341 attached to the inner wall of the sealed cavity 32 and extending from the condensation section 31c to the evaporation section 31a; a spiral liquid guiding microchannel 342 disposed on the inner wall of the sealed cavity 32, the spiral direction of the spiral liquid guiding microchannel 342 matching the rotation direction of the shaft 31; and a liquid collection area 343 disposed at the lower end of the condensation section 31c for collecting the working liquid 33 and guiding it to the spiral liquid guiding microchannel 342.

[0029] In this embodiment, the capillary core layer 341 can be a sintered metal powder layer, a metal fiber layer, a woven mesh layer, a composite capillary layer, or a combination of two or more of these layers, providing continuous capillary force so that the liquid can still be pulled back to the evaporation section 31a when the drill bit rotates, stops, or changes its attitude. The spiral direction of the spiral liquid guiding microchannel 342 matches the rotation direction of the shaft 31, and the guide angle spiral helix angle is controlled within the range of 15-45 degrees. This ensures that when the condensed working fluid 33 is subjected to the effect of rotation near the inner wall, it will not stagnate too much near the condensation section 31c. The liquid will be guided downwards along the channel to the evaporation section 31a. Both work simultaneously. The capillary core layer 341 is responsible for continuous liquid absorption, and the spiral liquid guiding microchannel 342 is responsible for accelerating liquid guiding in the rotating state, resulting in a more stable liquid return. The liquid return structure 34 may also include a liquid collection area 343 located at the lower end of the condensation section 31c. This area is an annular groove machined into the inner wall of the cavity to collect the working liquid 33 condensed from the upper part. The lower edge of the groove smoothly transitions to the inner wall of the transition section, forming a funnel-shaped guiding surface, which facilitates the flow of liquid from the groove into the spiral liquid guiding microchannel below. The presence of the liquid collection area 343 can reduce the accumulation of liquid at the junction of the condensation section 31c and the transition section 31b, making the liquid return path smoother and the liquid replenishment of the evaporation section 31a more timely.

[0030] As a preferred embodiment, the liquid return structure 34 further includes a liquid replenishment transition zone disposed on the upper part of the evaporation section 31a and a liquid pool disposed at the bottom of the evaporation section 31a.

[0031] In this embodiment, the liquid output from the spiral groove evenly penetrates into the capillary core layer in the liquid replenishment transition zone and is finally distributed to the circumference of the evaporation section. This can prevent the return liquid from being concentrated on a certain groove path and causing other places to dry out locally. The small liquid pool or buffer volume set at the bottom of the evaporation section is used to absorb short-term liquid volume fluctuations, which is more suitable for high-frequency drilling conditions.

[0032] As a preferred embodiment, the self-circulating heat dissipation structure 4 further includes a housing 42 disposed on the shaft 31, an air guide shroud 43 disposed on the inner wall of the housing 42, located above the finned disk 41 and forming an air inlet, and an air outlet 44 disposed through the housing 42 near the outer end of the finned disk 41; the outlet of the air outlet 44 faces the direction of the tangent of the shaft 31.

[0033] In this embodiment, the difference from the basic model is that a housing 42, an air guide shroud 43, and an air outlet 44 are added to the outer periphery of the condenser section 31c. This is suitable for scenarios where the space above the head allows to cover the condenser section and where further improvement in heat dissipation stability is desired. The housing 42 is fixed to the outer mounting part of the shaft 31, such as on the support base in the area where the condenser section 31c is located, or on a non-rotating mounting part adjacent to the shaft 31. The housing 42 itself does not rotate with the shaft 31. The material can be aluminum alloy, and the inner diameter should be larger than the outer diameter of the finned disk 41 to allow for airflow. The air guide shroud 43 is set on the inner wall of the housing 42 and is located above the finned disk 41, leaving a gap between it and the finned disk 41. This gap forms an air inlet. The air guide shroud is an annular truncated cone shroud that is larger at the bottom and smaller at the top. The distance between the lower edge and the upper surface of the finned disk 41 should ensure air entry while avoiding excessive gaps that would cause ineffective airflow dispersion. Air outlets 44 are disposed throughout the housing 42, located near the outer end of the finned disk 41, and there can be multiple outlets. Each outlet 44 can be configured as a strip-shaped hole, an arc-shaped hole, or a fan-shaped hole, with the outlet facing the tangential direction of the shaft 31, guiding hot air away from the housing and outwards along the flow trend formed by the rotation.

[0034] As a preferred embodiment, the drill tip cutting part 1 and the heat-conducting part 2 are connected by a low thermal resistance method, which is integrally machined, brazed, or interference-fitted.

[0035] In this embodiment, the drill tip cutting part 1 is the starting point of the heat source. If the thermal resistance of the connection interface is too large, the temperature fluctuation of the front end will be greater, and the heat dissipation capacity of the rear end of the temperature control spindle 3 will be difficult to exert. Therefore, a low thermal resistance connection method must be adopted.

[0036] As a preferred embodiment, the finned disk 41 includes a plurality of radial fins 411 symmetrically distributed along the axis 31, and a guide angle is provided at the end of the radial fins 411.

[0037] In this embodiment, the air guide angle is approximately 5 to 15 degrees. When combined with the tangential air outlet 44, it creates a smoother exhaust direction inside the housing 42. When the finned disk 41 rotates, the air at the outer end is driven first, and the outer air is discharged from the air outlet 44. The local pressure inside the housing 42 decreases, and fresh air from the top and middle is replenished from the air inlet between the air guide shroud 43 and the finned disk 41. This forms a self-circulating airflow without the aid of an independent fan.

[0038] As a preferred embodiment, the working fluid 33 is deionized water, ethanol, acetone, or a mixture thereof.

[0039] In this embodiment, for blended fabrics, the working fluid can be changed from pure water to a water-ethanol mixture. The purpose of adding ethanol is to lower the saturation temperature of the working fluid, so that phase change heat transfer can be carried out efficiently at a lower temperature, thereby further reducing the drill tip temperature.

[0040] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the present invention.

Claims

1. A cutting head drill, characterized in that, include: The drill tip cutting section (1) is located at the lower end of the drill bit and is used to contact and penetrate the fabric. A heat-conducting part (2) is disposed at the upper end of the drill tip cutting part (1) and is used to transfer the heat generated by the drill tip cutting part (1) upward; The temperature control spindle (3) includes a shaft (31) disposed at the upper end of the heat-conducting part (2), a sealed cavity (32) disposed inside the shaft (31), and a working fluid (33) encapsulated in the sealed cavity (32). The shaft (31) is divided into an evaporation section (31a), a transition section (31b) and a condensation section (31c) along the axial direction from bottom to top. The inner wall of the sealed cavity (32) is provided with a liquid return structure (34) for returning the condensed working fluid (33) to the evaporation section (31a). The self-circulating heat dissipation structure (4) includes a finned disk (41) fixed to the outer periphery of the condensation section (31c) and rotating coaxially with the shaft (31). The heat-conducting part (2) is a detachable structure, including a thermal resistance block (21) and a connecting handle (22) disposed on the thermal resistance block (21) and screwed to the lower end of the shaft (31).

2. The cutting head drill according to claim 1, characterized in that, The liquid return structure (34) includes a capillary core layer (341) attached to the inner wall of the sealed cavity (32) and extending from the condensation section (31c) to the evaporation section (31a).

3. A cutting head drill according to claim 2, characterized in that, The return structure (34) further includes a spiral liquid guiding micro-groove (342) disposed on the inner wall of the sealed cavity (32), wherein the spiral direction of the spiral liquid guiding micro-groove (342) matches the rotation direction of the shaft (31).

4. A cutting head drill according to claim 3, characterized in that, The return structure (34) further includes a collection area (343) located at the lower end of the condensation section (31c) for collecting the working fluid (33) and guiding it to the spiral liquid guiding microchannel (342).

5. A cutting head drill according to claim 1, characterized in that, The self-circulating heat dissipation structure (4) also includes a housing (42) disposed on the shaft (31), an air guide shroud (43) disposed on the inner wall of the housing (42), located above the finned disk (41) and forming an air inlet, and an air outlet (44) disposed through the housing (42) near the outer end of the finned disk (41).

6. A cutting head drill according to claim 5, characterized in that, The outlet (44) is oriented toward the tangent of the shaft (31).

7. A cutting head drill according to claim 1, characterized in that, The drill tip cutting part (1) and the heat-conducting part (2) are connected by a low thermal resistance method, which is integrally processed, brazed, or interference-fitted.

8. A cutting head drill according to claim 1, characterized in that, The finned disk (41) includes a plurality of radial fins (411) symmetrically distributed along the axis (31), and a guide angle is provided at the end of the radial fins (411).

9. A cutting head drill according to claim 1, characterized in that, The working fluid (33) is deionized water, ethanol, acetone or a mixture thereof.

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