A hot field assisted machining milling cutter cooling device

Abstract

The present application relates to the field of milling processing, disclose a kind of hot field auxiliary processing milling cutter cooling device, including milling cutter and the guide piece of being movably connected with milling cutter;The inner wall of the milling cutter is provided with passageway, the inner wall of the guide piece is provided with accommodating cavity, when the milling cutter is connected with the guide piece, the passageway is communicated with the accommodating cavity, the guide piece is used to be connected with cryogenic gas tank body by delivery pipe;When working, low-temperature carbon dioxide gas enters the passageway of the inner wall of the milling cutter after entering the accommodating cavity by the delivery pipe, so that the inner wall of the milling cutter extends to the whole cutter and is cooled;Low-temperature carbon dioxide gas significantly reduces the temperature of the milling cutter from inside, fundamentally inhibits the main thermal mechanism leading to tool failure, allows to use higher cutting speed and feed rate without worrying about the rapid failure of tool due to overheating. Significantly improve metal removal rate, shorten processing time, improve production efficiency.

Description

Technical Field

[0001] This invention relates to the field of milling, and in particular to a thermal field-assisted milling cutter cooling device. Background Technology

[0002] Milling is a core process in metal cutting. This process achieves precise material removal from the workpiece through the relative motion of a rotating multi-edged tool and the workpiece, enabling the machining of various complex geometric features such as planes, curved surfaces, threads, and gears. Heat-assisted machining, exemplified by laser-assisted machining, can significantly reduce cutting forces and improve surface quality. However, during machining, the plastic deformation of the material, frictional heat generation, and laser irradiation generate a large amount of heat. The heat propagation path within the machining system is complex and dynamically changing, leading to localized high-temperature hotspots due to factors such as thermal conductivity. The resulting non-uniform temperature field in the heated machining system induces complex thermal deformation, adversely affecting machining accuracy, tool performance, and surface integrity. In particular, the high-temperature environment of heat-assisted machining leads to abnormally accelerated tool wear, increasing tool costs, reducing production efficiency, and limiting the application of related technologies in actual industrial production. Summary of the Invention

[0003] Therefore, the technical problem to be solved by this invention is that: after the process system is heated, it generates an uneven temperature field, which causes complex thermal deformation and has an adverse effect on machining accuracy, tool performance, surface integrity, etc. In particular, the high temperature environment assisted by the thermal field will cause abnormally accelerated tool wear, increase tool cost, reduce production efficiency, and limit the application of related technologies in actual industry.

[0004] The above-mentioned technical problems are solved by the following technical solution: This invention proposes a thermal field-assisted milling cutter cooling device, which includes a milling cutter and a guide member movably connected to the milling cutter; the inner wall of the milling cutter is provided with a channel, and the inner wall of the guide member is provided with a receiving cavity. When the milling cutter is connected to the guide member, the channel is connected to the receiving cavity. The guide member is used to connect to a cryogenic gas tank through a delivery pipe. During operation, the cryogenic gas enters the receiving cavity through the delivery pipe and then enters the channel on the inner wall of the milling cutter, so that the cooling extends from the inner wall of the milling cutter to the entire tool.

[0005] In a preferred embodiment of the thermal field-assisted milling cutter cooling device of the present invention: the guide includes a connecting block, a first connecting hole and a second connecting through hole disposed on the connecting block; the receiving cavity includes a straight cavity disposed between the first connecting hole and the second connecting through hole and a first air guiding cavity disposed within the connecting block; the straight cavity is connected to the first air guiding cavity, and the first connecting hole is used to connect to the conveying pipe.

[0006] In a preferred embodiment of the thermal field-assisted milling cutter cooling device of the present invention: the first air guide cavity is provided with at least one air outlet hole, and the air outlet hole is connected to the second connecting hole.

[0007] In a preferred embodiment of the thermal field-assisted milling cutter cooling device of the present invention: a tool holder is inserted into the second connecting through hole, and the two ends of the tool holder extending out of the second connecting hole are the first end and the second end, respectively.

[0008] In a preferred embodiment of the thermal field-assisted milling cutter cooling device of the present invention: a collet is provided on the inner wall of the port of the second end, and the port of the second end is fixed to the inner wall of the second end by a threaded connection with a nut; the collet is used to hold the end of the milling cutter.

[0009] In a preferred embodiment of the thermal field-assisted machining milling cutter cooling device of the present invention: an air guide chamber is provided on the inner wall of the cutter holder, and at least one set of air guide holes are provided on the cutter holder, wherein the air guide chamber is connected to the air guide holes.

[0010] In a preferred embodiment of the thermal field-assisted milling cutter cooling device of the present invention: when the tool holder is inserted into the second connecting through hole, the space between the periphery of the outer wall of the tool holder located on the inner wall of the second connecting through hole and the periphery of the inner wall of the second connecting through hole is a second air guide cavity, and the air guide through hole is located in the second air guide cavity.

[0011] In a preferred embodiment of the thermal field-assisted milling cutter cooling device of the present invention: the channel on the inner wall of the milling cutter includes a first channel and an air outlet channel. The first channel is provided in one set, and the air outlet channel is provided in at least two sets. The air inlet end of the first channel is located at the top of the milling cutter. The air inlet ends of the air outlet channels are all connected to the tail end of the first channel, and the air outlet ends of the air outlet channels are evenly distributed around the central axis of the milling cutter on the outer wall of the tail end of the milling cutter.

[0012] In a preferred embodiment of the thermal field-assisted machining milling cutter cooling device of the present invention: at least four sets of channels are provided on the inner wall of the milling cutter, the air inlet end of the channel is provided on the end face of the inner wall of the milling cutter, and the air outlet end of the channel is evenly distributed around the central axis of the milling cutter on the outer wall of the milling cutter.

[0013] In a preferred embodiment of the thermal field-assisted milling cutter cooling device of the present invention: a large sleeve is fitted onto the outer wall of the first end of the cutter holder, and a small sleeve is fitted onto the outer wall of the second end of the cutter holder.

[0014] The beneficial effects of this invention are as follows: the low-temperature gas significantly reduces the temperature of the milling cutter from the inside, fundamentally suppressing the main thermal mechanisms that lead to tool failure; during operation, since gaseous carbon dioxide does not affect the heating effect of the thermal field in heat-assisted machining, higher cutting speeds and feed rates are allowed, significantly improving the metal removal rate, shortening the machining time, and increasing production efficiency. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments of the present invention will be briefly described below. Obviously, the drawings described below only relate to some embodiments of the present invention and are not intended to limit the present invention. Wherein: Figure 1 A schematic diagram showing the connection between the thermal field-assisted machining milling cutter cooling device and the cryogenic gas tank is shown; Figure 2 A schematic diagram of the operating status of the thermal field-assisted machining milling cutter cooling device is shown; Figure 3 A cross-sectional view of the connecting block of the thermal field-assisted machining milling cutter cooling device is shown; Figure 4 A cross-sectional view of the connection between the tool holder and collet in the thermal field-assisted machining milling cutter cooling device is shown. Figure 5 A schematic diagram showing the connection between the collet and the milling cutter in the thermal field-assisted milling cutter cooling device is shown. Figure 6 A schematic diagram of the internal channel structure of the milling cutter in the thermal field-assisted machining milling cutter cooling device is shown. Figure 7 The image shows a top view of the collet and the milling cutter in a thermal field-assisted milling cutter cooling device.

[0016] In the diagram: 1. Tool holder; 11. Gas guide chamber; 12. Gas guide through hole; 2. Large sleeve; 3. Guide component; 31. Connecting block; 32. First connecting hole; 33. Second connecting through hole; 311. Straight cavity; 331. First gas guide chamber; 34. Gas outlet through hole; 35. Second gas guide chamber; 4. Small sleeve; 5. Milling cutter; 51. Channel; 511. Tool body channel; 512. Side and rear tool face channel; 6. Cryogenic gas tank; 61. Tank pressure gauge; 62. Gas phase outlet; 7. Second connecting pipe; 8. Pressure reducing valve; 81. Adjusting knob; 82. Pressure gauge; 9. Delivery pipe; 10. Collet; 101. Rubber stopper; 13. Nut; 21. Laser emitting device; 211. Laser emitting head. Detailed Implementation

[0017] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0018] The terminology used in this invention is that which is currently widely used in the art in consideration of the function of the invention; however, these terms may vary according to the intent of those skilled in the art, precedent, or new technology in the art. Furthermore, specific terms may be chosen by the applicant, and in such cases, their detailed meanings will be described in the detailed description of the invention. Therefore, the terms used in this specification should not be construed as simple names, but rather based on their meanings and the overall description of the invention.

[0019] Reference Figure 1 , Figure 2 and Figure 6 This embodiment provides a cooling device for a milling cutter 5, including a milling cutter 5 and a guide 3 movably connected to the milling cutter 5. The inner wall of the milling cutter 5 is provided with a channel 51, and the inner wall of the guide 3 is provided with a receiving cavity. When the milling cutter 5 is connected to the guide 3, the channel 51 is connected to the receiving cavity.

[0020] Reference Figure 3 The guide 3 includes a connecting block 31, a first connecting hole 32 and a second connecting through hole 33 disposed on the connecting block 31; the receiving cavity includes a straight cavity 311 disposed between the first connecting hole 32 and the second connecting through hole 33 and a first air guiding cavity 331 disposed within the connecting block 31; the straight cavity 311 is connected to the first air guiding cavity 331, and the first connecting hole 32 is used to connect to the delivery pipe 9.

[0021] Reference Figure 4 The second connecting hole 33 is into which the knife handle 1 is inserted. The two ends of the knife handle 1 that extend out of the second connecting hole are the first end and the second end, respectively. The outer wall of the first end of the knife handle 1 is fitted with a large sleeve 2, and the outer wall of the second end of the knife handle 1 is fitted with a small sleeve 4.

[0022] Reference Figure 5 The inner wall of the second end port is provided with a collet 10, and the collet 10 is fixed to the inner wall of the second end port by threaded connection with the nut 13; the collet 10 is used to hold the end of the milling cutter 5, and the end of the collet 10 is provided with a rubber plug, which can prevent gas leakage.

[0023] The inner wall of the handle 1 is provided with a gas guiding chamber 11, and the handle 1 is provided with at least one set of gas guiding holes 12, which are connected to the gas guiding chamber 11 and the gas guiding holes 12. In this embodiment, six sets of gas guiding holes 12 are provided as an example for explanation.

[0024] The connection method between the tool holder 1 and the guide 3 is as follows: Using the tool holder 1 as a frame, the first end of the tool holder 1 is first nested with the large sleeve 2. Then, the tool holder 1 is inserted into the second connecting through hole 33 of the connecting block 31. Finally, the outer wall of the second end of the tool holder 1 is nested with the small sleeve 4. Next, the collet 10 is placed along the second end of the tool holder 1 into the inner wall of the tool holder 1. Then, the collet 10 clamps the end of the milling cutter 5. After the collet 10 is connected to the end of the milling cutter 5, it is connected to the tool holder 1 through the nut 13. Thus, the collet 10 is fixed inside the nut 13 and the tool holder 1. Then, the nut 13 and the tool holder 1 are connected by a threaded fastener. It should be noted that when both the large sleeve 2 and the small sleeve 4 are fitted onto the outer wall of the tool holder 1, the position of the guide 3 on the tool holder 1 can be fixed, ensuring that the air guide hole 12 on the tool holder 1 and the second connecting through hole 33 on the connecting block 31 are aligned.

[0025] Furthermore, when the tool holder 1 is inserted into the second connecting through hole 33, the space between the periphery of the outer wall of the tool holder 1 located on the inner wall of the second through hole and the periphery of the inner wall of the second connecting through hole 33 forms the second gas guiding cavity 35, and the gas guiding through hole 12 is located within the second gas guiding cavity 35. It should be noted that, since the tool holder 1 and the connecting block 31 will rotate relative to each other, that is, although the gas guiding through hole 12 on the tool holder 1 and the gas outlet through hole 34 on the connecting block 31 are on the same plane, they will move relative to each other during operation and are not always in a state of one-to-one alignment. If the second cavity is not provided, the low-temperature gas cannot smoothly enter the internal cavity of the tool holder 1. After the second gas guiding cavity 35 is provided, as long as the gas enters from the gas outlet through hole 34 and fills the second gas guiding cavity 35, and the cooperation between the connecting block 31 and the tool holder 1 ensures that no leakage occurs, the gas can enter the internal cavity of the tool holder 1 through the gas guiding through hole 12, thereby avoiding the influence of the relative rotation between the connecting block 31 and the tool holder 1.

[0026] Furthermore, refer to Figure 1 and Figure 2 The guide component 3 is used to connect to the cryogenic carbon dioxide tank 6 via the delivery pipe 9. One end of the delivery pipe 9 is threadedly connected to the first connecting hole 32 of the connecting block 31, and the other end of the delivery pipe 9 is connected to the pressure reducing valve 8 via a pneumatic connector. The pressure reducing valve 8 is also connected to the second connecting pipe 7 via a pneumatic connector, and the other end of the second connecting pipe 7 is connected to the gas phase port of the cryogenic carbon dioxide tank 6. Both the delivery pipe 9 and the second connecting pipe require heat insulation treatment, such as by applying heat insulation cotton to their outer walls.

[0027] In this embodiment, the cryogenic gas is used to cool the milling cutter by introducing it into the inner wall of the cutter. Any cryogenic gas that meets this condition can be used in this device; cryogenic carbon dioxide is used as an example in this embodiment. During operation, the cryogenic carbon dioxide gas enters the receiving cavity through the delivery pipe 9 and then enters the channel 51 on the inner wall of the milling cutter 5, allowing cooling to extend from the inner wall of the milling cutter 5 to the entire tool. Finally, it is ejected from the outlet end of the internal channel of the milling cutter 5 and enters the atmosphere. Thus, it achieves tool cooling, reduces tool wear, and extends its service life, without affecting the heating effect of the laser / thermal field assisted softening material. This is an effective means to realize and promote laser / thermal field assisted processing technology.

[0028] In this embodiment, the cryogenic carbon dioxide gas supplied by the cryogenic carbon dioxide tank 6 is introduced into the internal channel 51 of the milling cutter 5 at a pressure of 0.6 MPa through a pipeline under the control of the pressure reducing valve 8. The cryogenic carbon dioxide gas overflows from the outlet end on the flank face of the milling cutter 5 through the internal channel 51. This achieves efficient cooling from inside the milling cutter 5, improves the surface properties of the machined material, reduces tool wear, and extends tool life. At the same time, the use of cryogenic carbon dioxide gas is also environmentally friendly.

[0029] Furthermore, refer to Figure 6 The channel 51 on the inner wall of the milling cutter 5 includes a first channel and an air outlet channel. The connection method between the first channel and the air outlet channel is as follows: Figure 6 As shown by the red lines in the diagram. There is one set of first channels, and at least two sets of exhaust channels. The air inlet ends of all exhaust channels are connected to the first channel. The air outlet ends of the exhaust channels are evenly distributed around the central axis of the milling cutter 5 on the outer wall of the milling cutter 5. In this embodiment, four sets of exhaust channels are used as an example. Two sets of exhaust channels are cutter body channels 511, and the other two sets are side and rear face channels 512. It should be noted that the four channels 51 are symmetrical in pairs. Figure 7 As shown. That is, the positions of the two tool body channels 511 differ by 180°, and the positions of the two side-rear tool face channels 512 also differ by 180°. Furthermore, as... Figure 7 As shown, the adjacent cutter body channel 511 and the side rear cutter face channel 512 are 90° apart. The air outlet channel is set in this way to ensure the uniformity of cooling of the entire end mill 5.

[0030] As an optional embodiment, the inner wall of the end mill 5 has at least four sets of channels 51. The air inlet of the channel 51 is located on the end face of the inner wall of the end mill 5, and the air outlet of the channel 51 is evenly distributed around the central axis of the end mill 5 on the outer wall of the end mill 5. The channel 51 is arranged in this way to ensure the uniformity of cooling of the end mill 5 as a whole.

[0031] Working process: The cooling device of the milling cutter 5 is connected to the lathe via the guide 3. The gas outlet of the cryogenic carbon dioxide tank 6 is opened, and cryogenic carbon dioxide gas is supplied to the cryogenic carbon dioxide tank 6 under the action of internal air pressure. At the same time, the liquid carbon dioxide in the tank continuously vaporizes. Utilizing the heat absorption process during the vaporization of liquid carbon dioxide, cryogenic carbon dioxide gas is generated, thus providing a stable and uniform cryogenic carbon dioxide gas for the entire device. The real-time air pressure inside the cryogenic carbon dioxide tank 6 can be seen through the tank pressure gauge 61. The cryogenic carbon dioxide gas reaches the pressure reducing valve 8 through the second connecting pipe 7 with good thermal insulation performance. The output rate of the cryogenic carbon dioxide gas is controlled by the adjusting knob 81 of the pressure reducing valve 8 to ensure that the output air pressure is stable at about 0.6 MPa. Subsequently, the low-temperature carbon dioxide gas enters the straight cavity 311 of the first connecting hole 32 of the guide member 3 through the delivery pipe 9, and then enters the first gas guide cavity 331 through the straight cavity 311. The low-temperature carbon dioxide gas fills the entire first gas guide cavity 331. When the handle 1 is inserted into the second connecting through hole 33, the space between the periphery of the outer wall of the handle 1 located on the inner wall of the second through hole and the periphery of the inner wall of the second connecting through hole 33 forms the second gas guide cavity 35. At this time, the low-temperature carbon dioxide gas in the first gas guide cavity 331 enters the second gas guide cavity 35 through the gas outlet hole 34. After the second gas guide cavity 35 is filled with low-temperature carbon dioxide gas, the low-temperature carbon dioxide gas enters the gas guide chamber 11 inside the handle 1 through the six gas guide holes 12 on the handle 1.

[0032] After the low-temperature carbon dioxide gas fills the gas guide chamber 11, it enters the channel 51 on the inner wall of the milling cutter 5 through the collet 10, thereby realizing that during the milling cutter 5 machining, the low-temperature carbon dioxide gas continuously passes through the inside of the milling cutter 5 and is finally ejected from the back face of the milling cutter 5 to cool the tool.

[0033] To ensure the cooling effect, low-temperature carbon dioxide gas needs to be introduced for pre-cooling 15 minutes before the formal processing, and the low-temperature carbon dioxide gas needs to be continuously introduced at a stable pressure throughout the entire processing process. Then, the laser emitting device 21 is activated to emit a laser for thermal assisted processing of the material.

[0034] It should be noted that this invention makes the chips brittle and easier to break by using low temperatures, which helps with chip breaking and removal, reducing the risk of chips entangled in the tool. Low temperatures also suppress thermal softening, thermal deformation, and built-up edge formation of the workpiece material. The inert environment prevents surface oxidation. This allows the milling cutter 5 to achieve lower surface roughness, higher surface integrity, and no oxidation or discoloration.

[0035] Carbon dioxide is a major component of air and is released directly into the atmosphere after use, causing no chemical pollution. There is no need to treat waste cutting fluid, oil mist, or oil residue. This completely eliminates environmental problems and treatment costs associated with cutting fluid, meeting the most stringent environmental regulations and sustainability requirements, resulting in a cleaner working environment.

[0036] Finally, it should be noted that the methods and devices described in detail above are merely embodiments, and those skilled in the art can modify these embodiments in different ways as long as they do not depart from the scope of the present invention.

Claims

1. A cooling device for milling cutters assisted by a thermal field, characterized in that: include, The milling cutter (5) and the guide (3) movably connected to the milling cutter (5); The milling cutter (5) has a channel (51) on its inner wall and a receiving cavity on its inner wall. When the milling cutter (5) is connected to the guide (3), the channel (51) is connected to the receiving cavity. The guide (3) is used to connect to the cryogenic gas tank (6) through the delivery pipe (9). During operation, low-temperature gas enters the receiving cavity through the delivery pipe (9) and then enters the channel (51) on the inner wall of the milling cutter (5), so that the gas extends from the inner wall of the milling cutter (5) to the entire tool for cooling.

2. The thermal field-assisted machining milling cutter cooling device according to claim 1, characterized in that: The guide (3) includes a connecting block (31), a first connecting hole (32) and a second connecting through hole (33) disposed on the connecting block (31); The accommodating cavity includes a straight cavity (311) disposed between the first connecting hole (32) and the second connecting through hole (33) and a first air guiding cavity (331) disposed within the connecting block (31). The straight cavity (311) is connected to the first air guide cavity (331), and the first connecting hole (32) is used to connect to the delivery pipe (9).

3. The thermal field-assisted milling cutter cooling device according to claim 2, characterized in that: The first air guide cavity (331) is provided with at least one air outlet (34), which is connected to the second connecting hole (33).

4. The thermal field-assisted machining milling cutter cooling device according to claim 3, characterized in that: The second connecting hole (33) is into which the knife handle (1) is inserted, and the two ends of the knife handle (1) extending out of the second connecting hole are the first end and the second end, respectively.

5. The thermal field-assisted milling cutter cooling device according to claim 4, characterized in that: A collet (10) is provided on the inner wall of the port at the second end, and the collet (10) is fixed to the inner wall of the second end by threaded connection with a nut (13); The collet (10) is used to hold the end of the milling cutter (5).

6. The cooling device for a heat-assisted machining milling cutter according to claim 5, characterized in that: The inner wall of the handle (1) is provided with an air guiding chamber (11), and the handle (1) is provided with at least one set of air guiding holes (12), and the air guiding chamber (11) is connected to the air guiding holes (12).

7. The thermal field-assisted machining milling cutter cooling device according to claim 6, characterized in that: When the handle (1) is inserted into the second connecting through hole (33), the space between the outer periphery of the handle (1) and the inner periphery of the second connecting through hole (33) is the second air guide cavity (35), and the air guide hole (12) is located in the second air guide cavity (35).

8. The thermal field-assisted machining milling cutter cooling device according to claim 7, characterized in that: The channel (51) on the inner wall of the milling cutter (5) includes a first channel and an air outlet channel. The first channel is provided in one set, and the air outlet channel is provided in at least two sets. The air inlet end of the first channel is located at the top of the milling cutter. The air inlet of each air outlet channel is connected to the tail end of the first channel, and the air outlet of each air outlet channel is evenly distributed around the central axis of the milling cutter (5) on the outer wall of the tail end of the milling cutter (5).

9. A cooling device for a milling cutter assisted by a thermal field according to claim 7, characterized in that: The inner wall of the milling cutter (5) has at least four sets of channels (51). The air inlet of the channel (51) is located on the end face of the inner wall of the milling cutter (5), and the air outlet of the channel (51) is evenly distributed around the central axis of the milling cutter (5) on the outer wall of the milling cutter (5).

10. A thermal field-assisted machining milling cutter cooling device according to claim 8 or 9, characterized in that: A large sleeve (2) is fitted onto the outer wall of the first end of the handle (1), and a small sleeve (4) is fitted onto the outer wall of the second end of the handle (1).

Images