A small ball-end milling cutter for finishing

Abstract

The present invention relates to the technical field of machining tools, and discloses a small ball-end milling cutter for fine machining, comprising an integrated tool rod and a ball head, wherein the ball head is provided with a V-shaped groove, and one side of the V-shaped groove is provided with an upper and lower tool mounting groove, wherein an upper blade and a lower blade are respectively installed in the upper and lower tool mounting grooves, and an infusion channel running through the tool rod and the ball head is provided at the center, an internal cooling nozzle is provided in the infusion channel for sliding up and down, a lower drainage port is provided on the side of the bottom of the internal cooling nozzle, an external drainage port is provided on the side of the middle section of the internal cooling nozzle, an external drainage channel is provided on the inner wall of the ball head, and the other end of the external drainage channel is connected to a side of the V-shaped groove opposite to the tool mounting groove; the problem that the coolant of the small ball-end milling cutter for fine machining is easy to flush iron chips into the preset hole and affect chip removal when drilling vertically and the existing coolant spraying method is not suitable for chip removal requirements during horizontal cutting is solved.

Description

Technical Field

[0001] The invention relates to the technical field of machining tools, in particular to a small ball-end milling cutter for fine machining. Background Art

[0002] In the field of precision manufacturing, small ball-end milling cutters, with their excellent surface machining capabilities and high-precision cutting performance, are widely used in key applications such as mold manufacturing, aerospace parts processing, and medical device precision component processing. As modern industry's requirements for product precision and surface quality continue to increase, higher standards are being placed on the stability, efficiency, and processing results of small ball-end milling cutters during the finishing process.

[0003] In actual machining operations, in response to the machining needs of some materials, when using a small ball-end milling cutter for vertical drilling operations, in order to ensure machining accuracy and tool life, rough machining is usually performed in advance to form a preset hole, and then the ball-end milling cutter is used for fine machining. However, in this process, in order to reduce the cutting temperature, reduce tool wear and improve the quality of the machined surface, it is necessary to continuously spray coolant into the cutting area. However, the existing coolant spraying method has obvious defects: when the coolant is sprayed downward, it is easy to form a strong impact force, which directly flushes the iron chips generated during the cutting process into the preset hole. Since the preset hole space is relatively closed, the iron chips that are flushed in are difficult to be discharged smoothly through the natural chip removal process, which not only causes the iron chips to accumulate in the preset hole, but also may cause secondary cutting of iron chips in the subsequent cutting process, scratching the machined surface, affecting the machining accuracy, and even increasing the tool load due to iron chip blockage, causing tool chipping and other faults, which seriously restricts machining efficiency and product quality.

[0004] At the same time, when a small ball-end milling cutter is used for horizontal cutting of materials, the cutting direction and force state change significantly, and the chip removal path also changes accordingly. At this time, the traditional coolant spraying method suitable for vertical drilling scenarios is difficult to adapt to the chip removal needs of horizontal cutting: on the one hand, the coolant spray angle and coverage range cannot be accurately aligned with the iron chips generated by horizontal cutting, resulting in poor chip removal effect; on the other hand, the coolant flow and pressure parameters are not adjusted according to the characteristics of horizontal cutting. Insufficient coolant may cause the cutting area temperature to be too high, and excessive coolant may disrupt the normal discharge trajectory of iron chips, further exacerbating the chip removal problem. This mismatch between the coolant spraying method and the diversified cutting method seriously affects the processing stability and reliability of small ball-end milling cutters in horizontal cutting operations, making it difficult to meet the finishing requirements under complex working conditions.

[0005] To sum up, the current ball end mills used for small finishing face the problems of poor chip discharge and inability to adapt to various cutting methods due to unreasonable coolant spraying methods in different processing scenarios such as vertical drilling and horizontal cutting. These problems have become the key bottlenecks restricting the improvement of their processing efficiency, precision and stability, and urgently need to be solved through technical improvements. Summary of the Invention

[0006] (1) Technical problems solved

[0007] In response to the shortcomings of the existing technology, the present invention provides a small ball-end milling cutter for fine machining, which has the advantages of adapting to various working conditions, accurately discharging iron chips, and stable chip cutting. It solves the problem that when a small ball-end milling cutter is used for fine machining, the coolant easily flushes iron chips into the preset holes and affects chip removal when drilling vertically, and the existing coolant spraying method is not suitable for chip removal requirements during horizontal cutting.

[0008] (2) Technical solution

[0009] To achieve the above object, the present invention provides the following technical solutions:

[0010] A small ball-end milling cutter for fine machining comprises an integrated tool shank and a ball head, the ball head being provided with a first V-shaped groove, one side of the first V-shaped groove being provided with an upper and lower tool mounting groove, an upper blade and a lower blade being mounted in the upper and lower tool mounting grooves respectively, an infusion channel running vertically through the tool shank and the ball head being provided at the center, an internal cooling nozzle being provided in the infusion channel for sliding up and down, a lower drainage port being provided on the side of the bottom of the internal cooling nozzle, an external drainage port being provided on the side of the middle section of the internal cooling nozzle, an external drainage channel being provided on the inner wall of the ball head, the other end of the external drainage channel being connected to a side of the first V-shaped groove opposite to the tool mounting groove;

[0011] When punching the material, the internal cooling nozzle protrudes downward into the reserved hole. At this time, the coolant is sprayed outward from the lower drain port and discharged from the bottom to the top. When cutting the surface of the material, the internal cooling nozzle retracts into the infusion channel. At this time, the coolant is sprayed from the external drain channel to the lower blade and the upper blade.

[0012] Preferably, the back blade surface of the lower blade installed in the knife groove is provided with a lower liquid channel, and the lower liquid channel is provided with a lower liquid outer channel at a position close to the outer surface of the ball head. The lower liquid outer channel includes an internal main channel and multiple perforations on the outer side. When punching and feeding, the perforation on the lower liquid outer channel located in the preset hole is the lower liquid inlet groove, and the perforation on the lower liquid outer channel that fits with the material is the lower liquid outlet groove. A part of the coolant surging upward in the preset hole enters the main channel of the lower liquid outer channel from the lower liquid inlet groove, and is discharged from the lower liquid outlet groove to the outer surface of the ball head.

[0013] Preferably, the position inside the lower liquid channel also includes a lower liquid inner channel, an inner drainage channel is further provided on the inner wall of the infusion channel, an inner drainage port is further provided on the inner cooling nozzle, the other end of the inner drainage channel is connected to the lower liquid inner channel, and the two knife mounting grooves are connected via a connecting channel;

[0014] The upper blade is installed in the blade groove and is provided with an upper liquid channel on its back surface. The upper liquid channel is provided with an upper liquid outer channel at a position close to the outer surface of the ball head. The upper liquid outer channel includes an internal main flow channel and a plurality of perforations on the outer side. The main flow of the upper liquid outer channel is connected to the communication channel.

[0015] When the material is surface cut, the internal cooling nozzle retracts into the infusion channel. At this time, the internal drainage port is aligned with the internal drainage channel. Part of the coolant in the internal cooling nozzle is discharged from the internal drainage channel into the lower liquid channel, and then discharged to the surface of the ball head from the perforation of the upper liquid outlet trough.

[0016] Preferably, the inner side of the upper liquid channel also includes an upper liquid inner channel, and the upper liquid inner channel is connected to the upper liquid outer channel through a blowing hole. The upper blade is a triangular arc-shaped tool, and the upper blade includes three arc-shaped edges, one of the edges of the upper blade is a cutter head, and the other two edges are installed in the knife groove, and an exhaust hole is provided on the knife groove at a corner away from the cutter head of the upper blade, and the exhaust hole is connected to the upper liquid inner channel, and an air guide groove is provided on at least one of the arc-shaped edges connected to the exhaust hole on the knife groove, and the depth of the air guide groove is progressive, and the depth of the air guide groove is shallower at the end close to the cutter head than at the end close to the exhaust hole, and the air guide groove is used to introduce the wind generated by the rotation into the upper liquid inner channel, and use the wind blown out of the blowing hole to accelerate the flow of coolant in the upper liquid outer channel.

[0017] Preferably, the ball head is further provided with a second V-groove, and the second V-groove and the first V-groove are evenly arranged on the outer surface of the ball head. A middle blade is installed on one side of the second V-groove, and the height of the middle blade is higher than the lower blade and lower than the upper blade.

[0018] Preferably, a heat dissipation channel with the same structure as the upper liquid outer channel is provided on the back of the middle blade, and the heat dissipation channel on the back of the middle blade is connected to the internal cooling nozzle, and the coolant in the internal cooling nozzle is used to continuously dissipate heat from the back of the middle blade.

[0019] Preferably, a drainage groove is provided at the bottom of the tool groove at a position on the outer surface of the ball head, and the drainage groove is used to spirally discharge the coolant flowing out of the upper liquid channel and the lower liquid channel to the outer surface of the ball head.

[0020] Preferably, a return spring is also provided on the internal cooling nozzle, one end of the return spring is fixed to the root of the internal cooling nozzle, and the other end is fixed to the inner wall of the infusion channel. The return spring allows the internal cooling nozzle to be hidden in the infusion channel when no external force is received.

[0021] Preferably, a block is provided at the top of the inner cooling nozzle, the diameter of the block is larger than the inner diameter of the top of the infusion channel, and a liquid inlet hole is provided on the block, and the liquid inlet hole is connected to the inside of the inner cooling nozzle.

[0022] Preferably, a guide groove is provided on the inner wall of the infusion channel, and a guide slider matching the guide groove is provided on the outer side of the internal cooling nozzle, and the guide slider is slidably provided in the guide groove.

[0023] (3) Beneficial effects

[0024] Compared with the prior art, the present invention provides a small ball-end milling cutter for fine machining, which has the following beneficial effects:

[0025] 1. The small ball-end milling cutter for fine machining is provided with an infusion channel penetrating the center of the tool rod and the ball head, and an internal cooling nozzle that can slide up and down is provided in the infusion channel. A lower drainage port is provided on the bottom side of the internal cooling nozzle, an external drainage port is provided on the side of the middle section, and an external drainage channel connected to the first V-groove is provided on the inner wall of the ball head, thereby realizing the function of switching the cooling mode according to the processing scenario. When punching and feeding the material, the internal cooling nozzle is used to penetrate into the preset hole, and the coolant is discharged from the preset hole to the outside, so that the iron chips are discharged from the inside to the outside. At the same time, when the internal cooling nozzle is pressed against the bottom of the preset hole, it also has a stabilizing effect on the milling cutter body. Secondly, when surface cutting is performed on the material, the material pushes the internal cooling nozzle back into the infusion channel, so that the coolant is sprayed from the external drainage channel to the lower blade and the upper blade, directly dissipating heat to the blade and improving the cooling efficiency, thereby realizing automatic switching of cooling modes under different cutting environments.

[0026] 2. By setting a lower liquid channel on the back surface of the lower blade, a lower liquid outer channel is set near the outer surface of the ball head. The lower liquid outer channel includes a main channel and multiple perforations. A lower liquid inlet groove and a lower liquid outlet groove are formed when punching and feeding, thereby realizing the secondary utilization and circulating cooling of the coolant. When punching the material, the lower blade is located at the bottom, so the cutting amount is large and the heat is fast. At this time, the coolant quickly cools the lower blade head position through the lower liquid outer channel.

[0027] 3. By setting a lower liquid inner channel on the inner side of the lower liquid channel, an inner drainage channel on the inner wall of the infusion channel, an inner drainage port on the inner cooling nozzle, the two knife mounting grooves are connected by a connecting channel, and an upper liquid channel and an upper liquid outer channel are set on the back surface of the upper blade, the cooling range during surface cutting is expanded. When surface cutting the material, the upper blade is located on the side, so the cutting amount is large and the heat is fast. At this time, the coolant first passes through the lower liquid inner channel and then through the upper liquid outer channel, thereby cooling the blade root of the lower blade and the blade head of the upper blade respectively. Therefore, the coolant is mainly used for the heat dissipation of the upper blade, and a small amount of cooling is performed on the lower blade, thereby realizing cooling distribution and balancing the heating rate of the lower blade and the upper blade.

[0028] 4. By setting an upper liquid inner channel on the inner side of the upper liquid channel, the upper liquid inner channel is connected to the upper liquid outer channel through the blowing hole, an exhaust hole is set at the knife groove away from the upper blade head, and a wind guide inclined groove with progressive depth is set at the edge of the knife groove, the function of accelerating the flow of coolant by rotating wind force is realized, and the airflow generated by the rotation is used to make the upper liquid inner channel generate airflow to the upper liquid outer channel. Under the action of the airflow, the flow rate of the coolant in the upper liquid outer channel is accelerated, thereby improving the cooling efficiency on the basis of the original mechanism. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic structural diagram of the internal cooling nozzle of the present invention when it slides out.

[0030] Figure 2 It is a schematic structural diagram of the present invention when cutting the first material vertically downward.

[0031] Figure 3 It is a partial enlarged view of the area in the figure of the present invention.

[0032] Figure 4 It is a schematic diagram of the structure of the internal cooling nozzle of the present invention when it is retracted.

[0033] Figure 5 It is a schematic structural diagram of the present invention when horizontally cutting the second material.

[0034] Figure 6 This is a partial enlarged view of area B in the figure of the present invention.

[0035] Figure 7 This is a sectional perspective view of the present invention, and the section area is at the position of the internal cooling nozzle 3.

[0036] Figure 8 It is a structural schematic diagram of the internal cooling nozzle of the present invention.

[0037] Figure 9 It is a structural schematic diagram of the tool rod and the ball head main body of the present invention.

[0038] Figure 10 This is a schematic diagram of the back structure of the lower blade and the upper blade of the present invention.

[0039] Figure 11 This is a sectional perspective view of the structure of the present invention, and the section area is located at the internal liquid channels of the lower blade and the upper blade.

[0040] Figure 12 For the present invention Figure 11 A partial enlarged view of .

[0041] Figure 13 It is a structural schematic diagram of the present invention and an enlarged view of the wind guide chute.

[0042] Figure 14It is a schematic structural diagram of the second V-groove of the present invention.

[0043] In the figure: 1, blade rod; 2, ball head; 21, first V-shaped groove; 22, infusion channel; 221, external drainage channel; 222, internal drainage channel; 23, blade mounting groove; 231, drainage groove; 232, wind guide inclined groove; 233, exhaust hole; 234, connecting channel; 24, second V-shaped groove; 3, internal cooling nozzle; 31, lower drainage port; 32, external drainage port; 33, internal drainage port; 34 , return spring; 4, lower blade; 41, lower liquid channel; 411, lower liquid outer channel; 412, lower liquid inner channel; 4111, lower liquid inlet trough; 4112, lower liquid outlet trough; 5, upper blade; 51, upper liquid channel; 511, upper liquid outer channel; 512, upper liquid inner channel; 5111, upper liquid outlet trough; 5121, blowing hole; 6, middle blade; 7, first material; 71, preset hole; 8, second material. DETAILED DESCRIPTION

[0044] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0045] In the description of the present invention, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limiting the present invention.

[0046] In addition, a fixed connection refers to a connection in which parts or components are fixed without any relative movement; a transmission connection refers to a connection method in which mechanical motion or torque is transmitted to other working parts through a transmission part; a sliding connection refers to a connection method in which two objects are in contact but not fixed and can slide relative to each other; a rotating connection refers to a connection method in which two objects are in contact but not fixed and can rotate relative to each other.

[0047] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features being referred to. Thus, features specified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0048] Example 1:

[0049] This embodiment provides a small ball-end milling cutter for fine machining, which has the following technical features.

[0050] See also Figure 1-14 A small ball-end milling cutter for fine machining comprises an integrated tool rod 1 and a ball head 2, wherein the ball head 2 is provided with a first V-shaped groove 21, and one side of the first V-shaped groove 21 is provided with an upper and lower tool groove 23, wherein an upper blade 5 and a lower blade 4 are respectively installed in the upper and lower tool grooves 23, and an infusion channel 22 is provided at the center thereof, which passes through the tool rod 1 and the ball head 2, and an internal cooling nozzle 3 is provided in the infusion channel 22 for sliding up and down. A lower drain port 31 is provided on the side of the bottom of the internal cooling nozzle 3, and an external drain port 32 is provided on the side of the middle section of the internal cooling nozzle 3. An external drain channel 221 is provided on the inner wall of the ball head 2, and the other end of the external drain channel 221 is connected to a side opposite to the tool groove 23 in the first V-shaped groove 21;

[0051] When punching the material, the inner cooling nozzle 3 protrudes downward into the reserved hole, and the coolant is sprayed outward from the lower drain port 31, and the coolant is discharged from the bottom to the top; when surface cutting the material, the inner cooling nozzle 3 retracts into the infusion channel 22, and the coolant is sprayed from the external drain channel 221 to the lower blade 4 and the upper blade 5.

[0052] Through the above improvements, first, when punching and feeding the material, the internal cooling nozzle 3 is used to penetrate into the preset hole 71, and the coolant is discharged outward from the preset hole 71, so that the iron chips are discharged from the inside to the outside. At the same time, when the internal cooling nozzle 3 is pressed against the bottom of the preset hole 71, it also has a stabilizing effect on the milling cutter body. Secondly, when the surface of the material is cut, the material pushes the internal cooling nozzle 3 back into the infusion channel 22, so that the coolant is sprayed from the external discharge channel 221 to the lower blade 4 and the upper blade 5, directly dissipating heat to the blade to improve the cooling efficiency, and realize automatic switching of cooling modes under different cutting environments.

[0053] It should be noted that the plane where the cutting surfaces of the lower blade 4 and the upper blade 5 are located after installation is in the same plane as the milling cutter rotation axis.

[0054] It should be noted that the punching feed refers to the finishing of a material such as the first material 7. Before the feed, it is necessary to perform rough machining on the first material 7 to punch a preset hole 71, and then use the small ball-end milling cutter for finishing of the present invention to perform finishing. At this time, the internal cooling nozzle 3 slides downward into the preset hole 71 under the impact of the coolant water flow, and the coolant is sprayed upward from the preset hole 71 to discharge the iron chips outward, so as to avoid the accumulation of iron chips in the preset hole 71 and affect the cutting; the surface Cutting refers to the horizontal or inclined cutting of the surface of a material such as the second material 8. At this time, the internal cooling nozzle 3 is pushed back into the infusion channel 22 by the second material 8, so that the external drainage port 32 is aligned with the external drainage channel 221. By setting a small annular groove at the end of the infusion channel 22, a small amount of coolant is sprayed from the lower drainage port 31 and the annular groove in the infusion channel 22 to the surface of the ball head 2, and most of the remaining coolant flows from the external drainage port 32 into the external drainage channel 221, and then sprayed toward the blade from the external drainage channel 221.

[0055] It should be noted that the inner bottom of the preset hole 71 is a semicircular cross-section or a groove is pre-drilled to match the size of the end of the internal cooling nozzle 3, so that the stability is improved when the end of the internal cooling nozzle 3 is against the bottom of the preset hole 71.

[0056] In an optional embodiment, the back blade surface of the lower blade 4 installed in the blade groove 23 is provided with a lower liquid channel 41, and the lower liquid channel 41 is provided with a lower liquid outer channel 411 at a position close to the outer surface of the ball head 2. The lower liquid outer channel 411 includes an internal main channel and multiple perforations on the outer side. When punching, the perforation on the lower liquid outer channel 411 located in the preset hole 71 is the lower liquid inlet groove 4111, and the perforation on the lower liquid outer channel 411 that is in contact with the material is the lower liquid outlet groove 4112. A part of the coolant surging upward in the preset hole 71 enters the main channel of the lower liquid outer channel 411 from the lower liquid inlet groove 4111, and is discharged from the lower liquid outlet groove 4112 to the outer surface of the ball head 2.

[0057] Through the above improvements, when punching the material, the lower blade 4 is located at the bottom, so the cutting amount is large and the heat is fast. At this time, the coolant quickly cools the cutter head position of the lower blade 4 through the lower liquid outer channel 411.

[0058] In an optional embodiment, the inner side of the lower liquid channel 41 further includes a lower liquid inner channel 412, an inner drainage channel 222 is further provided on the inner wall of the infusion channel 22, and an inner drainage port 33 is further provided on the inner cooling nozzle 3. The other end of the inner drainage channel 222 is connected to the lower liquid inner channel 412, and the two tool mounting grooves 23 are connected via a connecting channel 234.

[0059] The upper blade 5 is installed in the blade groove 23 and is provided with an upper liquid channel 51 on its back surface. The upper liquid channel 51 is provided with an upper liquid outer channel 511 at a position close to the outer surface of the ball head 2. The upper liquid outer channel 511 includes an internal main channel and multiple perforations on the outer side. The main channel of the upper liquid outer channel 511 is connected to the communication channel 234.

[0060] When the material is surface cut, the internal cooling nozzle 3 retracts into the infusion channel 22. At this time, the internal drainage port 33 is aligned with the internal drainage channel 222. A portion of the coolant in the internal cooling nozzle 3 is discharged from the internal drainage channel 222 into the lower liquid channel 412, and then discharged to the surface of the ball head 2 from the perforation of the upper liquid outlet groove 5111.

[0061] Through the above improvements, when the surface of the material is cut, the upper blade 5 is located on the side, so the cutting amount is large and the heat is fast. At this time, the coolant first passes through the lower liquid inner channel 412 and then through the upper liquid outer channel 511, thereby cooling the blade root of the lower blade 4 and the blade head of the upper blade 5 respectively. In this way, the coolant is mainly used for the heat dissipation of the upper blade 5, and a small amount of cooling is performed on the lower blade 4, realizing cooling distribution and balancing the heating speed of the lower blade 4 and the upper blade 5.

[0062] In an optional embodiment, the inner side of the upper liquid channel 51 further includes an upper liquid inner channel 512, and the upper liquid inner channel 512 is connected to the upper liquid outer channel 511 through the blowing hole 5121. The upper blade 5 is a triangular arc-shaped tool. The upper blade 5 includes three arc-shaped edges. One edge of the upper blade 5 is a cutter head, and the other two edges are installed in the knife groove 23. The knife groove 23 is provided with an exhaust hole 233 at a corner away from the cutter head of the upper blade 5. The exhaust hole 233 is provided at a corner away from the cutter head of the upper blade 5. 33 is connected to the upper liquid inner channel 512, and an air guide inclined groove 232 is provided on at least one of the arc-shaped edges connected to the exhaust hole 233 on the tool groove 23. The depth of the air guide inclined groove 232 is in a progressive relationship. The depth of the air guide inclined groove 232 at the end close to the tool head is shallower than that at the end close to the exhaust hole 233. The air guide inclined groove 232 is used to introduce the wind generated by the rotation into the upper liquid inner channel 512, and use the wind blown out of the blowing hole 5121 to accelerate the flow of the coolant in the upper liquid outer channel 511.

[0063] Through the above improvements, by setting the wind guide inclined groove 232 and the exhaust hole 233, the air flow generated by the rotation is utilized to make the upper liquid inner channel 512 generate air flow to the upper liquid outer channel 511, and under the action of the air flow, the flow rate of the coolant in the upper liquid outer channel 511 is accelerated, thereby accelerating the cooling efficiency on the basis of the original mechanism.

[0064] In an optional embodiment, a second V-groove 24 is further provided on the ball head 2, and the second V-groove 24 and the first V-groove 21 are evenly arranged on the outer surface of the ball head 2. A middle blade 6 is installed on one side of the second V-groove 24, and the height of the middle blade 6 is higher than the lower blade 4 and lower than the upper blade 5.

[0065] In an optional embodiment, a heat dissipation channel with the same structure as the upper liquid outer channel 511 is provided on the back of the middle blade 6, and the heat dissipation channel on the back of the middle blade 6 is connected to the internal cooling nozzle 3, and the coolant in the internal cooling nozzle 3 is used to continuously dissipate heat from the back of the middle blade 6.

[0066] In an optional embodiment, a drainage groove 231 is provided at the bottom of the tool groove 23 on the outer surface of the ball head 2 , and the drainage groove 231 is used to spirally discharge the coolant flowing out of the upper liquid channel 51 and the lower liquid channel 41 to the outer surface of the ball head 2 .

[0067] In an optional embodiment, a return spring 34 is further provided on the internal cooling nozzle 3, one end of the return spring 34 is fixed to the root of the internal cooling nozzle 3, and the other end is fixed to the inner wall of the infusion channel 22. The return spring 34 allows the internal cooling nozzle 3 to be hidden in the infusion channel 22 when no external force is received.

[0068] In an optional embodiment, a block is provided at the top of the internal cooling nozzle 3 , the diameter of the block is larger than the inner diameter of the top of the infusion channel 22 , and a liquid inlet hole is provided on the block, which is connected to the interior of the internal cooling nozzle 3 .

[0069] It should be noted that the block can prevent the inner cooling nozzle 3 from sliding out of the liquid infusion channel 22, and the liquid inlet hole ensures that the coolant can smoothly enter the inner cooling nozzle 3, making the cooling system work more reliable.

[0070] In an optional embodiment, a guide groove is provided on the inner wall of the infusion channel 22, and a guide slider matching the guide groove is provided on the outer side of the internal cooling nozzle 3, and the guide slider is slidably provided in the guide groove.

[0071] It should be noted that the cooperation between the guide groove and the guide slider can ensure the stability of the internal cooling nozzle 3 when sliding up and down in the infusion channel 22, avoid its deviation or rotation, and ensure the accurate injection direction of the coolant.

[0072] Furthermore, an elastic buffer pad is provided at the bottom of the inner cooling nozzle 3. The elastic buffer pad is made of high temperature resistant rubber material. When punching, the elastic buffer pad contacts the bottom of the preset hole 71.

[0073] It should be noted that by providing an elastic buffer pad, when the punching and feeding internal cooling nozzle 3 hits the bottom of the preset hole 71, the rigid collision between the two can be reduced, playing a buffering and protective role, and extending the service life of the milling cutter and the material.

[0074] It is further provided that the number of perforations of the lower liquid outer channel 411 and the upper liquid outer channel 511 are 3 to 5, and are evenly distributed along the length direction of the blade.

[0075] It should be noted that clarifying the number and distribution of perforations can ensure that the coolant is distributed more evenly on the blade, improve the stability of the cooling effect, and also facilitate standardized operations during production.

[0076] It is further provided that a positioning pin is provided in the knife groove 23, and positioning holes matching the positioning pin are provided on the lower blade 4 and the upper blade 5, and the positioning pin is inserted into the positioning hole.

[0077] It should be noted that the cooperation between the positioning pin and the positioning hole can further improve the installation stability of the lower blade 4 and the upper blade 5 in the blade installation groove 23, prevent the blades from being displaced during the cutting process, and ensure cutting accuracy.

[0078] Furthermore, flow control valves are provided at the lower drain port 31 and the outer drain port 32 of the inner cooling nozzle 3, and the flow control valves automatically adjust the flow of the coolant according to the cutting speed of the milling cutter.

[0079] It should be noted that the flow control valve can adjust the coolant flow according to the change of cutting speed, increase the flow rate to enhance the cooling effect during high-speed cutting, and reduce the flow rate to save coolant during low-speed cutting, thereby realizing the rational use of coolant.

[0080] It is further provided that a spiral chip removal groove is provided on the outer surface of the ball head 2 between the first V-shaped groove 21 and the second V-shaped groove 24 , and the spiral direction of the spiral chip removal groove is consistent with the rotation direction of the milling cutter.

[0081] It should be noted that the spiral chip groove can generate directional chip removal force when the milling cutter rotates, and discharge the iron chips generated during the cutting process in time, avoiding the accumulation of iron chips in the cutting area and affecting the cutting effect and tool life.

[0082] It is further provided that the outer side of the knife rod 1 is provided with anti-slip lines, and the anti-slip lines are evenly distributed in a ring shape.

[0083] It should be noted that the anti-slip texture can increase the friction between the tool bar 1 and the installation equipment, prevent the milling cutter from slipping during installation and use, and improve the safety and stability of operation.

[0084] Working principle: Through the structural design of the integrated tool bar 1 and the ball head 2, combined with the slidable internal cooling nozzle 3 and the multi-channel cooling system, efficient operation and intelligent cooling switching in different cutting scenarios are achieved. When punching and feeding the material, the internal cooling nozzle 3 slides downward under the impact of the coolant and protrudes into the preset hole 71. At this time, the coolant is ejected from the lower drain port 31 at the bottom of the internal cooling nozzle 3 and discharged from the bottom to the top, which not only discharges the iron chips from the inside to the outside to avoid accumulation, but also stabilizes the milling cutter by pressing the internal cooling nozzle 3 against the bottom of the preset hole 71; at the same time, the lower liquid channel 41 on the back of the blade 4 will use the coolant rising upward from the preset hole 71, enter through the lower liquid inlet groove 4111 of the lower liquid outer channel 411, and be discharged from the lower liquid outlet groove 4112, so as to quickly cool the cutting head of the lower blade 4 with a large cutting volume and fast heat generation. During surface cutting, the material pushes the inner cooling nozzle 3 back to the infusion channel 22, and the coolant flows out from the external drainage port 32 in the middle section of the inner cooling nozzle 3, and is directly sprayed onto the lower blade 4 and the upper blade 5 through the external drainage channel 221 on the inner wall of the ball head 2, thereby achieving precise heat dissipation of the blades; in this state, the inner drainage port 33 on the inner cooling nozzle 3 is opposite to the inner drainage channel 222 of the infusion channel 22, and the coolant can enter the lower liquid inner channel 412 through the inner drainage channel 222, and then enter the upper liquid outer channel 511 through the connecting channel 234, cooling the root of the lower blade 4 and the cutter head of the upper blade 5 respectively, thereby balancing the heat generation of the two; at the same time, when the milling cutter rotates, the air guide groove 232 on the tool mounting groove 23 guides the airflow into the upper liquid inner channel 512, and blows it into the upper liquid outer channel 511 through the blowing hole 5121, thereby accelerating the flow of coolant to improve the cooling efficiency. The entire process automatically switches the cooling mode by changing the position of the internal cooling nozzle 3. Combined with the design that the lower blade 4 and the upper blade 5 are coplanar with the rotation axis, cutting accuracy and operation stability are guaranteed.

[0085] To sum up, the small ball-end milling cutter for fine machining is provided with an infusion channel 22 passing through the center of the tool rod 1 and the ball head 2, and an internal cooling nozzle 3 that can slide up and down is provided in the infusion channel 22. The bottom side of the internal cooling nozzle 3 is provided with a lower drainage port 31, and the middle side is provided with an external drainage port 32. The inner wall of the ball head 2 is provided with an external drainage channel 221 connected to the first V-shaped groove 21, which realizes the function of switching the cooling mode according to the processing scene. When punching and feeding the material, the internal cooling nozzle 3 is used to penetrate into the preset hole 71, and the coolant is discharged from the preset hole 71 to the outside, so that the iron chips are discharged from the inside to the outside. At the same time, when the internal cooling nozzle 3 is pressed against the bottom of the preset hole 71, it also has a stabilizing effect on the milling cutter body. Secondly, when the surface of the material is cut, the material pushes the internal cooling nozzle 3 back into the infusion channel 22, so that the coolant is sprayed from the external drainage channel 221 to the lower blade 4 and the upper blade 5, directly dissipating heat to the blade to improve the cooling efficiency, and realize automatic switching of cooling modes under different cutting environments.

[0086] The small ball-end milling cutter for fine machining is provided with a lower liquid channel 41 on the back cutting surface of the lower blade 4, and a lower liquid outer channel 411 is provided near the outer surface of the ball head 2 of the lower liquid channel 41. The lower liquid outer channel 411 includes a main channel and multiple perforations. When punching, a lower liquid inlet groove 4111 and a lower liquid outlet groove 4112 are formed, thereby realizing the secondary utilization and circulating cooling of the coolant. When punching the material, the lower blade 4 is located at the bottom, so the cutting amount is large and the heat is fast. At this time, the coolant quickly cools the cutting head position of the lower blade 4 through the lower liquid outer channel 411.

[0087] The small ball-end milling cutter for fine machining has a lower liquid inner channel 412 provided on the inner side of the lower liquid channel 41, an inner drainage channel 222 provided on the inner wall of the infusion channel 22, an inner drainage port 33 provided on the inner cooling nozzle 3, and the two tool mounting grooves 23 are connected by a connecting channel 234. The upper liquid channel 51 and the upper liquid outer channel 511 are provided on the back surface of the upper blade 5, thereby expanding the cooling range during surface cutting. When surface cutting the material, the upper blade 5 is located on the side, so the cutting amount is large and the heat is fast. At this time, the coolant first passes through the lower liquid inner channel 412 and then passes through the upper liquid outer channel 511, thereby cooling the blade root of the lower blade 4 and the blade head of the upper blade 5 respectively, so that the coolant is mainly used for heat dissipation of the upper blade 5, and a small amount of cooling is performed on the lower blade 4, thereby achieving cooling distribution and balancing the heating rates of the lower blade 4 and the upper blade 5.

[0088] The small ball-end milling cutter for fine machining is provided with an upper liquid inner channel 512 on the inner side of the upper liquid channel 51, the upper liquid inner channel 512 is connected to the upper liquid outer channel 511 through the blowing hole 5121, the tool groove 23 is provided with an exhaust hole 233 away from the cutter head of the upper blade 5, and the edge of the tool groove 23 is provided with an air guide inclined groove 232 with progressive depth, thereby realizing the function of utilizing rotating wind force to accelerate the flow of coolant, utilizing the airflow generated by the rotation to make the upper liquid inner channel 512 generate airflow to the upper liquid outer channel 511, and under the action of the airflow, the flow rate of the coolant in the upper liquid outer channel 511 is accelerated, thereby improving the cooling efficiency on the basis of the original mechanism.

[0089] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or device comprising the element.

[0090] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A small ball-end milling cutter for fine machining, comprising an integrated tool bar (1) and a ball head (2), wherein the ball head (2) is provided with a first V-shaped groove (21), wherein one side of the first V-shaped groove (21) is provided with an upper and lower tool groove (23), wherein an upper blade (5) and a lower blade (4) are respectively installed in the upper and lower tool grooves (23), characterized in that: The knife rod (1) and the ball head (2) are provided with an infusion channel (22) running through the center, an internal cooling nozzle (3) is provided in the infusion channel (22) so as to slide up and down, a lower drainage port (31) is provided on the side of the bottom of the internal cooling nozzle (3), an external drainage port (32) is provided on the side of the middle section of the internal cooling nozzle (3), an external drainage channel (221) is provided on the inner wall of the ball head (2), and the other end of the external drainage channel (221) is connected to a side of the first V-shaped groove (21) opposite to the knife mounting groove (23); When punching and cutting the material, the internal cooling nozzle (3) protrudes downward into the reserved hole; when surface cutting the material, the internal cooling nozzle (3) retracts into the infusion channel (22).

2. A small ball end mill for finishing according to claim 1, characterized in that: The lower blade (4) is installed on a back surface of the blade in the blade groove (23) and is provided with a lower liquid channel (41). The lower liquid channel (41) is provided with a lower liquid outer channel (411) at a position close to the outer surface of the ball head (2). The lower liquid outer channel (411) includes an internal main flow channel and a plurality of perforations on the outer side. During punching and feeding, the perforation on the lower liquid outer channel (411) located within the preset hole (71) is the lower liquid inlet trough (4111), and the perforation on the lower liquid outer channel (411) that is in contact with the material is the lower liquid outlet trough (4112).

3. A small ball end mill for finishing according to claim 2, characterized in that: The position inside the lower liquid channel (41) also includes a lower liquid inner channel (412), an inner drainage channel (222) is also provided on the inner wall of the infusion channel (22), and an inner drainage port (33) is also provided on the inner cooling nozzle (3), the other end of the inner drainage channel (222) is connected to the lower liquid inner channel (412), and the two knife grooves (23) are connected via a communication channel (234); The upper blade (5) is installed on the back blade surface in the blade groove (23) and is provided with an upper liquid channel (51). The upper liquid channel (51) is provided with an upper liquid outer channel (511) at a position close to the outer surface of the ball head (2). The upper liquid outer channel (511) includes an internal main channel and a plurality of perforations on the outer side. The main channel of the upper liquid outer channel (511) is connected to the connecting channel (234). When the internal cooling nozzle (3) is retracted into the infusion channel (22), the internal drainage port (33) is aligned with the internal drainage channel (222).

4. A small ball end mill for finishing according to claim 3, characterized in that: The inner side of the upper liquid channel (51) further includes an upper liquid inner channel (512), the upper liquid inner channel (512) being connected to the upper liquid outer channel (511) via an air blowing hole (5121), the upper blade (5) being a triangular arc-shaped tool, the upper blade (5) including three arc-shaped edges, one of the edges of the upper blade (5) being a cutting head, and the other two edges being mounted in a knife groove (23), an exhaust hole (233) being provided on a corner of the knife groove (23) away from the cutting head of the upper blade (5), the exhaust hole (233) being connected to the upper liquid inner channel (512); An air guiding inclined groove (232) is provided on at least one of the arc-shaped edges of the knife mounting groove (23) connected to the exhaust hole (233). The depth of the air guiding inclined groove (232) at one end close to the knife head is shallower than that at the other end close to the exhaust hole (233).

5. A small ball end mill for finishing according to claim 4, characterized in that: The ball head (2) is further provided with a second V-shaped groove (24), the second V-shaped groove (24) and the first V-shaped groove (21) being evenly arranged on the outer surface of the ball head (2), and a middle blade (6) is mounted on one side of the second V-shaped groove (24), the middle blade (6) being higher than the lower blade (4) and lower than the upper blade (5).

6. A small ball end mill for finishing according to claim 5, characterized in that: A heat dissipation channel having the same structure as the upper liquid outer channel (511) is provided on the back of the middle blade (6). The heat dissipation channel on the back of the middle blade (6) is connected to the internal cooling nozzle (3), and the coolant in the internal cooling nozzle (3) is used to continuously dissipate heat from the back of the middle blade (6).

7. A small ball end mill for finishing according to claim 4, characterized in that: A drainage groove (231) is provided at the bottom of the knife groove (23) at a position on the outer surface of the ball head (2), and the drainage groove (231) is used to spirally discharge the coolant flowing out of the upper liquid channel (51) and the lower liquid channel (41) to the outer surface of the ball head (2).

8. The small ball end mill for finishing according to claim 4, characterized in that: The inner cooling nozzle (3) is also provided with a return spring (34), one end of the return spring (34) is fixed to the root of the inner cooling nozzle (3), and the other end is fixed to the inner wall of the infusion channel (22). The return spring (34) allows the inner cooling nozzle (3) to be hidden in the infusion channel (22) when no external force is applied.

9. The small ball end mill for finishing according to claim 4, characterized in that: A block is provided at the top of the inner cooling nozzle (3), the diameter of the block being larger than the inner diameter of the top of the liquid infusion channel (22), and a liquid inlet hole is provided on the block, the liquid inlet hole being communicated with the interior of the inner cooling nozzle (3).

10. A small ball end mill for finishing according to claim 4, characterized in that: A guide chute is provided on the inner wall of the infusion channel (22), and a guide slider matching the guide chute is provided on the outer side of the inner cooling nozzle (3), and the guide slider is slidably arranged in the guide chute.

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